Exploring Self-Perceived Socio-Emotional Competences Following PBL in Secondary Education

Abstract

Contemporary education increasingly emphasises the development of Social and Emotional Learning (SEL) competencies alongside academic achievement, recognising their importance for students’ well-being, interpersonal relationships, and lifelong success. Project-Based Learning (PBL) is frequently presented as a pedagogical approach capable of fostering these competencies through collaboration, active engagement, and authentic learning experiences. However, empirical evidence regarding the extent to which these socio-emotional benefits emerge through participation in project work remains inconclusive. This study examined changes in students’ self-perceived socio-emotional competencies following participation in PBL intervention in secondary education. A one-group pre-test–post-test pre-experimental design was employed with 38 students aged 12–14 from a public secondary school in Andalusia, Spain. Students participated in four interdisciplinary PBL projects, each comprising approximately 10–12 sessions and implemented across the first two terms of the 2024–2025 academic year. Self-perceived SEL competencies were assessed using the 30-item Social and Emotional Learning Scale, and data were analysed using Wilcoxon signed-rank tests, Mann–Whitney U tests and Spearman’s rank correlations. No statistically significant pre-test–post-test differences were detected in self-awareness, social awareness, relationship skills, or responsible decision making. Self-control showed a statistically significant decrease in the individual Wilcoxon analysis, with a moderate effect size. No statistically significant gender differences were detected in the magnitude of change. The five competencies were positively associated at both measurement points, although these analyses did not test whether the correlational pattern remained unchanged over time. Rather than questioning the socio-emotional potential of PBL, these findings challenge assumptions regarding the automatic emergence of measurable SEL gains through project participation alone. They highlight the need for further controlled research into the pedagogical conditions under which PBL may support socio-emotional development, including intentional SEL integration, teacher preparation, structured collaborative scaffolding, and performance-based assessment.

1. Introduction

In recent decades, international debates on education have highlighted the urgent need to move beyond traditional, transmission-based models of teaching toward approaches that actively engage learners in the construction of knowledge. These shifts respond to the demand for deeper, more meaningful learning and to the need to cultivate students’ reflective capacity and promote interaction with peers and the wider community (Sánchez-García, 2022; Zambrano Briones et al., 2022). Within this context, PBL has emerged as a prominent pedagogical innovation. It is claimed to promote collaboration, critical thinking, creativity, and problem-solving, situating knowledge within authentic, student-driven inquiries (Blumenfeld et al., 1991; Thomas, 2000).

At the same time, education systems are increasingly expected to address the holistic development of learners, placing SEL at the core of twenty-first-century schooling. Research demonstrates that SEL enhances students’ social adaptation and supports academic achievement, as emotional regulation and interpersonal competencies influence cognitive engagement and performance (Berger et al., 2014). According to the Collaborative for Academic, Social, and Emotional Learning (CASEL), SEL comprises five interrelated areas of competence: self-awareness, self-management, social awareness, relationship skills, and responsible decision making. These skills are most effectively developed when integrated into everyday pedagogical practices, including classroom climate and teaching methodologies, rather than being treated as add-ons (CASEL, 2020). This raises the question of whether pedagogical approaches that naturally create socio-emotional demands can contribute to SEL development even when these competencies are not explicitly taught.

PBL offers opportunities for embedding SEL into classroom practices. By engaging students in authentic projects that require cooperation, negotiation, and critical reflection, PBL creates contexts where socio-emotional competencies may be developed alongside cognitive ones (CASEL, 2024). However, while PBL is frequently presented as a context that may support SEL development, evidence regarding the extent to which these socio-emotional outcomes emerge through participation in project work remains inconclusive (Condliffe et al., 2017). Often, projects prioritise the production of visible artefacts over deeper processes such as reflection, empathy, or decision making, resulting in a gap between stated intentions and actual implementation (Sánchez-García & Angosto, 2026). Although collaborative learning and authentic tasks may create favourable conditions for socio-emotional development, such benefits cannot be assumed to emerge automatically from project participation alone.

A further question is whether participation in PBL projects is accompanied by changes in specific SEL competencies when SEL is not explicitly established as an instructional objective. PBL requires students to regulate their behaviour, collaborate with peers, consider others’ perspectives, negotiate relationships, and make decisions. However, opportunities to mobilise these competencies do not necessarily imply their systematic development. Examining SEL under these conditions may help clarify whether participation in project work alone is accompanied by changes in students’ self-perceived socio-emotional competencies or whether explicit SEL objectives may be needed.

The present study contributes to this debate by examining changes in students’ self-perceived socio-emotional competencies after participating in a PBL intervention in secondary education. Specifically, it explores changes across different SEL competencies, potential differences associated with gender, and patterns of association among SEL competencies before and after participation in project work. Using a one-group pre-test–post-test pre-experimental design involving two intact classroom groups participating in the same PBL programme, the study provides exploratory evidence regarding the extent to which participation in PBL experiences is accompanied by changes in students’ socio-emotional self-perceptions.

By examining the PBL intervention in which SEL was not explicitly established as an instructional objective, the study highlights the need for further research into the role of explicit SEL objectives, teacher preparation, reflective practices, and socio-emotional scaffolding within PBL environments. Accordingly, the study addresses the following research questions:

RQ1.

To what extent do students’ self-perceived SEL competencies change following participation in a PBL intervention in secondary education?

RQ2.

Are some self-perceived SEL competencies more sensitive to change than others following participation in PBL experiences?

RQ3.

Do changes in students’ self-perceived SEL competencies differ according to gender?

RQ4.

What patterns of association among self-perceived SEL competencies are observed before and after participation in the PBL intervention?

2. Theoretical Framework

2.1. Project-Based Learning: Foundations and Characteristics

Project-Based Learning is understood as a comprehensive, student-centred educational approach, oriented toward the active construction of knowledge through authentic, collaborative, and interdisciplinary experiences. It seeks to transform not only how students learn, but also how education itself is conceptualised, aiming to address contemporary challenges and prepare students to contribute to societal change (Lenz et al., 2015).

Its theoretical underpinnings are rooted in socio-constructivism, which views learning as an active and socially mediated process. From Piaget’s perspective (Piaget, 1970), learning entails the continuous reorganisation of cognitive structures through processes of assimilation and accommodation in response to experiences that challenge prior schemas. In PBL, such experiences take the form of complex, contextualised problems that require exploration, inquiry, and conceptual restructuring. Likewise, Vygotsky (1978) emphasised that cognitive development is intrinsically linked to social and cultural interaction, proposing key concepts such as the Zone of Proximal Development (ZPD) as a framework for understanding the role of social mediation in learning. Building on this foundation, Bruner (1978) introduced the concept of scaffolding to describe how tailored guidance from teachers and peers enables students to achieve levels of performance they would not attain independently, a central principle in the collaborative dynamics inherent to PBL.

Dewey’s (1938) pragmatist perspective provides a further theoretical foundation, advocating for an education connected to real and relevant problems, positioning experience as the driving force of learning. His disciple, Kilpatrick (1918), formalised this proposal through the “Project Method,” emphasising inquiry and the active resolution of meaningful problems. These ideas are reflected in contemporary PBL, which integrates challenge, collaboration, guided inquiry, critical reflection, and the public presentation of products as key milestones in the learning process (Krajcik & Blumenfeld, 2006; Larmer et al., 2015).

In this vein, PBL not only offers an alternative to traditional instruction but also connects curricular content with real-life contexts and fosters essential 21st-century competencies such as collaboration, autonomy, and critical thinking (Sánchez-García & Reyes-de-Cózar, 2025).

2.2. Key Dimensions of PBL: Procedural, Cognitive, and Socio-Emotional

The recent scholarly literature on PBL underscores the need for a holistic approach that transcends the traditional emphasis on procedural aspects and instead integrates cognitive and socio-emotional dimensions into project learning (Sánchez-García & Reyes-de-Cózar, 2025). Widely accepted, PBL frameworks identify structural elements, such as authentic driving questions, sustained inquiry, authenticity, student voice and choice, ongoing reflection, and the public presentation of results, as fundamental to ensuring internal coherence (Larmer et al., 2015). However, an overemphasis on these procedural components risks relegating other essential dimensions.

In fact, recent studies indicate that, although the socio-emotional dimension is well represented in the literature, it often remains implicit rather than being systematically addressed in practice (Condliffe et al., 2017). Similarly, cognitive and metacognitive components, crucial for deeper learning, often lack explicit and systematic attention, revealing an imbalance that undermines PBL’s transformative capacity (Sánchez-García & Angosto, 2026).

Consequently, translating the theoretical potential of PBL into measurable educational outcomes remains a challenge in many educational contexts. Frequently, projects labelled as PBL prioritise the production of visible artefacts over essential formative processes such as critical reflection, student voice, or deep cognitive engagement (Condliffe et al., 2017). In this regard, the socio-emotional dimension becomes particularly relevant. Within the SEL framework, socio-emotional development involves competencies related to self-awareness, self-management, social awareness, relational skills, and responsible decision making (CASEL, 2020).

While these competencies are widely associated in the literature with students’ well-being and inclusive educational settings (Baines et al., 2021), their effective development cannot be assumed to occur spontaneously within collaborative learning contexts such as PBL. The recent literature has increasingly highlighted the importance of examining the pedagogical conditions under which socio-emotional gains emerge, including the possible contribution of explicit objectives, guided practice, and reflective processes (Sánchez-García & Angosto, 2026).

Likewise, the cognitive component, far from being addressed in isolation, is closely linked to socio-emotional development, insofar as competencies such as critical thinking and the ability to analyse alternatives are intrinsically related to responsible decision making, one of SEL’s five core competencies. From this perspective, PBL should not be reduced to a well-structured procedural sequence; instead, it should operate as an environment in which academic learning, socio-emotional development, and informed decision making are integrated as complementary axes (CASEL, 2024).

Thus, a holistic approach to PBL not only organises tasks and timelines but may also incorporate opportunities for socio-emotional development, recognising it as an important component of meaningful learning and of preparing students to face the relational, ethical, and emotional challenges inherent in academic and social life in the twenty-first century (Baines et al., 2021).

2.3. Socio-Emotional Learning Within PBL

SEL is defined as the process by which students acquire and effectively apply the knowledge, attitudes, and skills needed to understand and manage their emotions, establish and maintain healthy relationships, demonstrate empathy toward others, set and achieve positive goals, and make responsible, ethical decisions (CASEL, 2020). This approach not only fosters students’ emotional and social development but also constitutes a core component of holistic learning, linking the affective, cognitive, and behavioural dimensions of human development.

According to Fernández-Martín et al. (2022), SEL is organised around five interrelated competencies: Self-awareness, understood as the ability to recognise one’s emotions, values, and strengths; Social awareness, which involves perspective-taking, empathy, and prosocial behaviour; Self-control, related to regulating emotions and behaviours in pursuit of long-term goals; Relationship skills, encompassing effective communication, cooperation, and conflict resolution; and Responsible decision making, which requires analysing situations critically, considering ethical consequences, and selecting actions that promote both individual and collective well-being. The term Self-control is used when referring to the present study, following the terminology of the Social and Emotional Learning Scale developed by Fernández-Martín et al. (2022). In contrast, Self-management is retained when referring to the CASEL framework, as this is the term used by CASEL for this core SEL competency.

Extensive research highlights SEL as a robust predictor of academic success, social adaptation, and psychological well-being (Jagers et al., 2019; Taylor et al., 2017). Within school contexts, systematic SEL implementation fosters inclusive and safe environments, improves social interactions, and reduces disruptive behaviour and emotional problems, factors that are especially relevant in secondary education, a stage marked by significant changes in identity, cognition, and social relationships (Durlak et al., 2011).

However, studies conducted in secondary education frequently report relatively high baseline levels of SEL competencies, regardless of the instructional methodology employed (Panadero et al., 2016). The use of self-report instruments to assess socio-emotional competencies has been associated with ceiling effects, whereby students, particularly in adolescence, tend to report high levels of self-awareness, empathy, communication, and decision making (Duckworth & Yeager, 2015). This self-perception may reflect students’ declarative understanding of SEL rather than their capacity to consistently transfer these skills to emotionally demanding or socially complex situations.

In this regard, research in developmental psychology indicates that although adolescents may demonstrate an explicit understanding of socio-emotional norms, such as emotional regulation, empathy, or responsible decision making, they may simultaneously struggle to apply these skills consistently in contexts characterised by social pressure, or interpersonal conflict (Crone & Dahl, 2012; Steinberg, 2014). This discrepancy has been related to the asynchronous development of cognitive control and socio-emotional systems during adolescence, which contributes to heightened emotional reactivity, sensitivity to peer evaluation, and contextual variability in behaviour (Blakemore & Mills, 2014; Casey et al., 2019).

This situation may help explain a paradox frequently reported in research on secondary education in which high self-reported levels of SEL coexist with indicators of emotional distress, impulsivity and relational difficulties (Duckworth & Yeager, 2015; Panadero et al., 2016).

Recent research has emphasised the integration of SEL into everyday pedagogical practices and academic content rather than treating it as a separate component of instruction. In this regard, the explicit integration of SEL into active methodologies such as PBL may provide opportunities for the simultaneous development of cognitive and socio-emotional competencies (Baines et al., 2021). This alignment positions SEL as a foundational condition for meaningful learning and for preparing students to address the relational, ethical, and emotional demands of 21st-century life (OECD, 2021). From this perspective, a focus on instruction rather than mere exposure to SEL-related experiences is essential both for improving students’ SEL development and for understanding why high perceived SEL levels may coexist with limited observable gains (Zieher et al., 2024).

The distinction between providing opportunities to use socio-emotional competencies and explicitly teaching these competencies is particularly relevant in PBL contexts where SEL is not established as an instructional objective. The socio-emotional demands inherent in project work do not necessarily imply the development of the competencies involved. This provides a theoretical basis for examining whether sustained participation in PBL is accompanied by changes in students’ self-perceived SEL competencies in the absence of explicit SEL instruction.

3. Materials and Methods

The present research adopted a quantitative, pre-experimental case study design using a one-group pre-test–post-test approach within a comprehensive educational intervention involving an interdisciplinary PBL intervention implemented in an authentic secondary education setting. This research was conducted within the framework of the Teaching Innovation Project “Designing Educational Pathways: Analysis and Development of Didactic Resources in Spanish for Project-Based Learning (PBL) and STEAM Projects”. For the implementation of the intervention, four projects aligned with the curricular content of the first cycle of secondary education were designed.

3.1. Project Design

The projects implemented within the framework of the present study were designed according to PBL principles, with the aim of integrating secondary education curricular content across different subject areas (Biology and Geology, Mathematics, Geography and History, and Spanish Language and Literature). The four projects were implemented in two separate first-year secondary education classes during the first and second terms of the 2024–2025 academic year. Each project comprised approximately 10–12 sessions. Sessions for each project were delivered three to four times per week, depending on the timetable of the subject involved. Five teachers participated in the implementation. Each project was led by the teacher responsible for the corresponding subject, with the Biology and Geology project jointly implemented by two teachers. Students worked in groups of four or five. These groups were formed by the teachers based on students’ characteristics, previous performance, and observed group functioning, with the aim of facilitating balanced and functional group compositions.

Each project was structured into progressive phases, ranging from the initial launch and motivational stage, based on the formulation of a driving question or challenge, through information gathering and preliminary research, knowledge construction and practical experimentation, to the presentation of outcomes and a process of collective reflection and evaluation.

Regarding their thematic focus, the projects addressed real-world issues and challenges closely linked to the Sustainable Development Goals (SDGs). These included the following projects: “Mathematics in Your Pocket: What If You Discovered That Your Phone Is Writing a Diary with Everything You Say?” in the subject of Mathematics; “Beyond Differences: How Can Communication and Art Be Used to Transform Inequalities into Opportunities for Change?” in Spanish Language and Literature; “If All Roads Lead to Rome, How Do We Get Out of It?” in Geography and History; and “How Can Plant Adaptations in Different Biomes Help Us Address Current Environmental Challenges and Promote Sustainability?” in Biology and Geology.

The projects followed a common Project-Based Learning (PBL) implementation framework developed within the CPBL Model (Sánchez-García et al., 2025). Implementation followed a five-stage process: (1) project launch, in which the driving question, context, and learning goals were established; (2) information gathering, during which students explored the topic and collected relevant data with teacher support and guidance; (3) information handling, which included categorising, examining, and integrating the data obtained; (4) project showcase, during which students developed and presented their final products to an audience; and (5) final assessment and reflection, during which the learning process and the final product were evaluated.

The researchers adopted a supervisory role, supporting the implementation of the projects in accordance with the initial proposal and addressing adjustments and refinements that arose during the process. However, no formal implementation-fidelity measure or systematic fidelity checklist was used to assess consistency across projects. The supervising teachers at the partner school primarily acted as facilitators and mediators, providing cognitive and linguistic scaffolding, guiding students in their investigation and analysis, supporting decision making and collaboration, and giving feedback during the different stages of the project. Students were progressively encouraged to take responsibility for planning, researching, producing, presenting, and reflecting on their work.

Although the projects incorporated collaborative work, authentic problems, public products, and opportunities for interaction commonly associated with socio-emotional development in the PBL literature, socio-emotional competencies were not established as explicit instructional objectives nor systematically assessed as part of project implementation. Consequently, the study provides an opportunity to explore the extent to which participation in PBL experiences may be associated with changes in students’ self-perceived SEL competencies in the absence of explicit SEL instruction.

The projects culminated in the production of tangible outcomes (digital blogs, scientific journals, murals, models, school gardens, and oral presentations), which were shared with the educational community. This external dissemination aimed not only to enhance students’ motivation and sense of purpose, but also to promote key socio-emotional competencies such as self-efficacy, assertive communication, cooperation, and social responsibility.

3.2. Sample

The sample consisted of 38 students enrolled in the first year of secondary education in Spain in a public school in Andalusia, which was involved in the Teaching Innovation Project and voluntarily agreed to participate in the study. The participants were aged between 12 and 14 years. Accordingly, a non-probabilistic intentional sampling strategy was employed, as participation was determined by the school’s involvement in the project. Inclusion in the analytic sample required participation in the PBL intervention and completion of both the pre-test and post-test assessments. The sample was composed of 55.3% male and 44.7% female students. To ensure anonymity, each participant was assigned an alphanumeric identification code.

3.3. Research Instrument and Fieldwork

To assess students’ socio-emotional competencies, the Social and Emotional Learning Scale developed and validated by Fernández-Martín et al. (2022) was employed. This instrument, originally designed by the authors and grounded in the CASEL socio-emotional competence framework, consists of 30 items distributed across five competencies: self-awareness, self-control, social awareness, relationship skills, and responsible decision making. In this study, the reported reliability is as follows: for the pre-test, α = 0.95; ω = 0.96 for Competency 1; α = 0.66; ω = 0.68. In Competency 2 α = 0.81; ω = 0.83. Regarding Competency 3 α = 0.89; ω = 0.90. For Competency 4 α = 0.85; ω = 0.86. Finally, in Competency 5, α = 0.84; ω = 0.84. For the post-test, α = 0.92 and ω = 0.92. Regarding the individual competencies, Competency 1 showed α = 0.68 and ω = 0.70, while Competency 2 presented α = 0.56 and ω = 0.55. Competency 3 yielded α = 0.84 and ω = 0.81. For Competency 4, the coefficients were α = 0.83 and ω = 0.84. Finally, Competency 5 demonstrated α = 0.83 and ω = 0.85.

In the present study, the scale was used to examine pre-test–post-test changes in students’ self-perceived socio-emotional competencies following their participation in the PBL experiences. Given the nature of the intervention which focused on interdisciplinary projects aligned with the secondary education curriculum, the instrument provided an appropriate framework for measuring students’ self-perceived socio-emotional competencies at the two measurement points. The adaptation of the scale was limited to the contextualisation of the instructions and its administration in digital format. As the original instrument was available in English, it was translated into Spanish for administration to the participating students. The translation was conducted by bilingual members of the research team and sought to preserve the conceptual meaning and content of the original items without modifying the constructs assessed or introducing new content.

The questionnaire required approximately 15 min to complete and was structured into two main sections. First, a set of sociodemographic questions was included to collect basic information about the sample, specifically age and gender. Second, the Socio-Emotional Learning Scale was administered, assessing the five CASEL SEL competencies using a 5-point Likert-type scale (1 = Strongly Disagree, 2 = Disagree, 3 = Neutral, 4 = Agree, 5 = Strongly Agree). Students were asked to indicate their level of agreement with each statement in both the pre-test and post-test administrations.

Data collection was carried out digitally using Google Forms, which facilitated efficient distribution and data management across the participating schools. Students completed the questionnaire during sessions organised by the collaborating teachers, under the supervision of the research team, whose members were available to clarify any questions about the interpretation of the items if necessary.

At the beginning of the questionnaire, students were asked to enter an anonymous alphanumeric code, which they generated themselves based on predefined initials and relevant dates. This procedure ensured participant anonymity for the researchers while allowing the matching of pre-test and post-test responses for each student. Of the 56 students who took part in the study at the beginning, 18 provided data at only one of the two measurement points (either pre-test or post-test). Because paired analyses required observations at both time points, these cases were excluded from the analytic sample. The final sample therefore consisted of 38 students who voluntarily participated in the educational experience and completed questionnaires at both measurement points. Given the exploratory and preliminary nature of the study, the aim was not to obtain a sample representative of the population, but rather to obtain an initial empirical examination of the SEL profiles of students before and after their participation in the Project-Based Learning experience. The sample size was therefore determined by the number of eligible students who participated in the intervention and completed both assessments. Data were collected throughout the 2024–2025 academic year. The pre-test was administered prior to the start of the PBL activities, and the post-test was conducted after the completion of the projects. Prior to data collection, the study received ethical approval from the Ethics Committee of Universidad Loyola Andalucía (reference no. 250303 CE25576; 11 March 2025). Parents or legal guardians received an information letter through the school administration explaining the purpose and procedures of the study, together with an informed consent form. Written parental consent was obtained before students participated in the study. In addition, immediately before questionnaire administration, students were informed orally about the purpose of the study and the voluntary nature of their participation. During questionnaire administration, members of the research team accompanied the students rather than their teachers to minimise teacher–student power asymmetries and reduce any perceived pressure to participate.

3.4. Data Analysis

The data were analysed using IBM SPSS Statistics, version 27 statistical software. First, descriptive statistical techniques (mean, standard deviation, variance, skewness, and kurtosis) were used to characterise the distribution of responses. The Wilcoxon signed-rank test, Mann–Whitney U test and Spearman’s non-parametric correlation coefficient were used to explore the relationship between the identified dimensions, given that the Likert scale is ordinal in nature and the variables did not have a normal distribution. This lack of normality was confirmed using the Kolmogorov–Smirnov test with Lilliefors significance correction, which yielded a value of p = 0.000 (≤0.05). Data analysis was performed using SPSS statistical software.

4. Results

This study adopted a pre-experimental, quantitative research design, incorporating descriptive, ex post facto and correlational analyses to analyse the evolution of secondary school students’ social-emotional learning in the context of implementing PBL methodology.

4.1. Pre-Test–Post-Test Changes in Socio-Emotional Competencies

The results of the competencies analysed are presented below in

Table 1. Competencies analysed in the study.

Competency	Mean Pre	SD Pre	Mean Post	SD Post	Δ (Post–Pre)
Self-awareness	3.88	0.73	3.73	0.71	−0.15
Social awareness	3.83	0.79	3.76	0.62	−0.07
Self-control	3.70	0.80	3.58	0.76	−0.12
Relationship skills	4.02	0.81	4.05	0.78	+0.03
Responsible decision making	3.94	0.83	3.98	0.75	+0.04

.

Overall, the descriptive analysis conducted before and after the intervention reveals very limited changes across the five socio-emotional competencies assessed (Table 1). Pre-test and post-test mean scores remain relatively stable, with slight decreases observed in self-awareness (Δ = −0.15), social awareness (Δ = −0.07), and self-control (Δ = −0.12). In contrast, small improvements are observed in relationship skills (Δ = +0.03) and responsible decision making (Δ = +0.04). Addressing RQ1, the findings indicate that the pre-test–post-test changes in students’ self-perceived socio-emotional competencies were generally small, with no statistically significant increases observed in four of the five competencies. Despite these minimal variations, mean scores at both measurement points fall within moderate-to-high ranges, indicating that students already displayed a relatively solid level of self-perceived socio-emotional competencies prior to the intervention. Standard deviations also remain stable between the pre-test and post-test, suggesting consistency in the distribution of scores and the absence of substantial changes in within-group variability. Regarding RQ2, no clear differential pattern of change across the socio-emotional competencies was identified, although self-control showed a statistically significant decrease. Although minor variations were observed, these changes were generally small and inconsistent in direction. However, the reduction in self-control was statistically significant and therefore warrants special attention. To determine whether students’ scores differed significantly between the pre-test and post-test, Wilcoxon signed-rank test was applied (

Table 2. Wilcoxon signed-rank test.

Competency	Negative Ranks (Post < Pre)	Positive Ranks (Post > Pre)	Z	Sig.	r
Self-awareness	2	3	−1.703	0.088	0.27
Social awareness	16	15	−0.590	0.555	0.09
Self-control	24	7	−2.426	0.015	0.39
Relationship skills	18	14	−0.113	0.910	0.02
Responsible decision making	11	14	−0.149	0.881	0.03

) with the effect size (r) considered moderate from r = 0.30 onwards. The analyses were conducted using a significance level of p < 0.05.

The individual Wilcoxon analyses detected no statistically significant pre-test–post-test differences in self-awareness, social awareness, relationship skills, or responsible decision making. Self-control scores decreased from pre-test (M = 3.70, SD = 0.80) to post-test (M = 3.58, SD = 0.76), Z = −2.426, unadjusted p = 0.015, r = 0.39. Given that five separate comparisons were conducted, this finding should be considered exploratory.

4.2. Gender-Based Differences in Socio-Emotional Competencies

To examine potential differences according to gender, the non-parametric Mann–Whitney U test was applied with the effect size (r), as the data did not meet the assumption of normality and the comparisons involved independent groups. The analysis was conducted for both pre-test and post-test scores across each of the socio-emotional competencies assessed. The analyses were conducted using a significance level of p < 0.05.

Table 3. Gender-based differences in socio-emotional competencies: pre-test and post-test comparisons.

Competencies	Mann–Whitney U	Wilcoxon W	Z	Sig.	r
Pre-Self-awareness	171.500	402.500	−0.206	0.836	0.03
Pre-Social awareness	159.500	390.500	−0.560	0.575	0.09
Pre-Self-control	159.500	312.500	−0.559	0.576	0.09
Pre-Relationship skills	174.500	405.500	−0.118	0.906	0.02
Pre-Responsible decision making	131.500	362.500	−1.386	0.166	0.22
Post-Self-awareness	124.500	277.500	−1.597	0.110	0.25
Post-Social awareness	169.000	322.000	−0.280	0.779	0.05
Post-Self-control	121.000	274.000	−1.692	0.091	0.27
Post-Relationship skills	170.500	323.500	−0.236	0.813	0.04
Post-Responsible decision making	141.500	372.500	−1.092	0.275	0.18

presents the obtained values for the U and W statistics, the Z value, and the associated significance levels.

The results indicate that no statistically significant differences were observed between male and female students in any of the five socio-emotional competencies, either at pre-test or at post-test (p > 0.05 in all cases). No statistically significant gender differences were detected in students’ scores at either measurement point. At pre-test, the competencies self-awareness, social awareness, self-control, relationship skills, and responsible decision making yielded p-values ranging from 0.166 to 0.906, well above the conventional threshold for statistical significance. Similarly, in the post-test, p-values ranged from 0.091 to 0.813, further indicating that no statistically significant differences between male and female students were detected. Differences in the magnitude of pre-test–post-test change according to gender were assessed by calculating individual change scores for each SEL competency (post-test score minus pre-test score) and comparing these scores between male and female students using Mann–Whitney U tests. There were no statistically significant gender differences in the magnitude of change for any of the five SEL competencies: self-awareness, U = 136.00, Z = 1.88, p = 0.061, r = 0.30; social awareness, U = 149.00, Z = 0.84, p = 0.409, r = 0.14; self-control, U = 135.50, Z = 1.89, p = 0.060, r = 0.31; relationship skills, U = 167.50, Z = 0.29, p = 0.776, r = 0.05; and responsible decision making, U = 145.50, Z = 1.02, p = 0.316, r = 0.17.

Overall, no statistically significant gender differences were detected in the magnitude of pre-test–post-test change for any of the five SEL competencies (RQ3).

To address RQ4 beyond mean-level analyses, the study examined the patterns of association among the five self-perceived SEL competencies at the pre-test and post-test measurement points.

4.3. Correlational Analysis of Socio-Emotional Competencies

Beyond mean-level changes, it was considered relevant to examine the relationships among the five socio-emotional competencies at the two measurement points. To this end, Spearman’s correlation coefficients were calculated for the five socio-emotional competencies at both the pre-test and post-test measurement points. This analysis examined the degree of association among the socio-emotional competencies at each measurement point. The findings provide descriptive information on the patterns of association among the competencies before and after the PBL experiences. The results of these analyses are presented in

Table 4. Spearman correlations among pre-test and post-test SEL competency scores.

			Pre-Self-Awareness	Pre-Social Awareness	Pre-Self-Control	Pre-Relationship Skills	Pre-Responsible Decision Making	Post-Self-Awareness	Post-Social Awareness	Post-Self-Control	Post-Relationship Skills
	Pre-Social awareness	ρ	0.721 **	--
		Sig.	0.000	.
	Pre-Self-control	ρ	0.730 **	0.783 **	--
		Sig.	0.000	0.000	.
	Pre-Relationship skills	ρ	0.565 **	0.680 **	0.753 **	--
		Sig.	0.000	0.000	0.000	.
	Pre-Responsible decision making	ρ	0.555 **	0.697 **	0.795 **	0.821 **	--
		Sig.	0.000	0.000	0.000	0.000	.
	Post-Self-awareness	ρ	0.623 **	0.635 **	0.700 **	0.475 **	0.526 **	--
		Sig.	0.000	0.000	0.000	0.003	0.001	.
	Post-Social awareness	ρ	0.319	0.432 **	0.454 **	0.396 *	0.420 **	0.490 **	--
		Sig.	0.051	0.007	0.004	0.014	0.009	0.002	.
	Post-Self-control	ρ	0.515 **	0.584 **	0.816 **	0.486 **	0.514 **	0.731 **	0.563 **	--
		Sig.	0.001	0.000	0.000	0.002	0.001	0.000	0.000	.
	Post-Relationship skills	ρ	0.496 **	0.712 **	0.710 **	0.758 **	0.682 **	0.547 **	0.549 **	0.592 **	--
		Sig.	0.002	0.000	0.000	0.000	0.000	0.000	0.000	0.000	.
	Post-Responsible decision making	ρ	0.514 **	0.686 **	0.740 **	0.642 **	0.803 **	0.527 **	0.532 **	0.620 **	0.739 **
		Sig.	0.001	0.000	0.000	0.000	0.000	0.001	0.001	0.000	0.000

* p < 0.05; ** p < 0.01.

.

At pre-test, the five self-perceived SEL competencies were positively and statistically significantly correlated. The correlation coefficients ranged from ρ = 0.555 to ρ = 0.821 (p < 0.001). The strongest correlation was observed between relationship skills and responsible decision making (ρ = 0.821), and the weakest between self-awareness and responsible decision making (ρ = 0.555), although the latter was also of moderate-to-high magnitude.

At post-test, the five competencies were again positively and statistically significantly associated, with values ranging from ρ = 0.490 to ρ = 0.739 (p ≤ 0.002). The strongest association was again observed between relationship skills and responsible decision making (ρ = 0.739), and the weakest between self-awareness and social awareness (ρ = 0.490).

Regarding the associations between scores across the two measurement points, positive and statistically significant associations were observed between several of the competencies. These results describe the associations observed both within each measurement point and across the two measurement points. However, as the correlation coefficients at the pre-test and post-test were not formally compared, these analyses do not allow us to determine whether the strength of the overall pattern of the associations remained stable or changed over time.

5. Discussion

The primary aim of this study was to examine pre-test–post-test changes in secondary school students’ self-perceived socio-emotional competencies following their participation in four PBL experiences. The study also explored whether some competencies were more sensitive to change than others, whether the magnitude of change differed according to gender, and what patterns of association among the SEL competencies were observed at the pre-test and post-test measurement points. Given the pre-experimental pre-test–post-test design, in which students from two intact classroom groups participated in the same PBL condition and no comparison group was included, the findings are interpreted as changes observed during the implementation period rather than as effects caused by PBL.

In response to RQ1, students’ self-perceived SEL scores showed limited pre-test–post-test variation overall. No statistically significant differences were detected in self-awareness, social awareness, relationship skills, or responsible decision making. In contrast, self-control scores decreased significantly from pre-test to post-test in the individual Wilcoxon signed-rank test. Thus, four of the five competencies showed relatively similar scores across the two measurement points, whereas self-control displayed a different pattern of change. However, the absence of statistically significant differences in the other four competencies should not be interpreted as conclusive evidence that no change occurred. The small sample limited statistical power and the precision with which potentially small changes could be estimated.

Regarding RQ2, self-control appeared to be the competency most sensitive to change, showing a statistically significant decrease in the individual Wilcoxon analysis, with a moderate effect size. The direction of this difference is relevant because it does not support an interpretation of general socio-emotional improvement during the study period. Nevertheless, the result should be interpreted cautiously. Although five separate pre-test–post-test comparisons were conducted, increasing the probability of identifying a statistically significant result, the decrease in self-control should be regarded as an exploratory finding that requires confirmation in studies with larger samples, appropriate comparison conditions, and statistical control for multiple testing.

Several tentative interpretations may help contextualise the limited variation observed in most competencies. First, the moderate-to-high baseline scores may have reduced the scope for detecting positive change, particularly when SEL was assessed through self-report. Self-report instruments primarily capture students’ perception of their competencies rather than their demonstrated capacity to apply them in socially and emotionally demanding situations. They may also be affected by social desirability and ceiling effects, especially when the competencies assessed are positively valued within educational contexts (Duckworth & Yeager, 2015; Panadero et al., 2016). Consequently, relatively high initial scores may reflect students’ declarative understanding of appropriate socio-emotional behaviour without necessarily indicating that they can consistently mobilise these competencies across contexts.

The decrease observed in self-control also warrants careful consideration. Project work requires students to plan, sustain effort, coordinate with peers, manage competing demands, and respond to difficulties over time (Guo et al., 2020). One possible interpretation is that participation in these demanding experiences made students more aware of the challenges involved in regulating their behaviour and maintaining effort, leading them to assess their self-control more critically at post-test. Alternatively, this result may reflect measurement variability, contextual influences during the academic year, or experiences unrelated to the projects. Because the study did not include classroom observations, performance-based assessments, qualitative evidence, or a comparison group, these possible explanations cannot be distinguished empirically.

From a developmental perspective, the findings should also be situated within the particular characteristics of adolescence. This developmental stage is characterised by asynchronous maturation of socio-emotional and cognitive control systems, heightened sensitivity to peer evaluation, and greater emotional reactivity (Blakemore & Mills, 2014; Casey et al., 2019; Crone & Dahl, 2012). Adolescents may understand socio-emotional expectations and perceive themselves as competent while experiencing difficulties regulating their emotions, relationships, and behaviour under conditions of stress, conflict, or social pressure. This distinction may be particularly relevant to self-control and reinforces the need to differentiate between perceived competence and demonstrated performance.

Socio-emotional competencies also develop within a broader ecology of social interactions that extends beyond any specific pedagogical approach. Secondary school students engage in collaborative tasks, discussions, negotiation, and reflective exchanges not only during PBL but also in other classroom, family, and social contexts. Their self-perceived SEL competencies are therefore likely to reflect accumulated experiences across multiple settings rather than participation solely in the projects examined in this study (Zieher et al., 2024). This broader developmental ecology may offer one possible explanation for the limited pre-test–post-test variation observed in most SEL competencies. However, because the study did not examine students’ experiences outside the projects or include a comparison group, this interpretation remains tentative.

A central consideration in interpreting the findings is the distinction between creating opportunities to mobilise socio-emotional competencies and intentionally teaching those competencies. PBL places students in situations that require collaboration, behavioural regulation, negotiation, shared decision making, and responsibility. However, the presence of these socio-emotional demands does not necessarily mean that students receive the explicit instruction, guided practice, feedback, and reflection required to transform experience into learning. In the projects examined in this study, SEL competencies were not established as explicit instructional objectives and were not systematically taught or assessed. The limited changes observed in most competencies are therefore consistent with the possibility that exposure to socio-emotional demands within project work may not, by itself, be sufficient to produce detectable changes in students’ self-perceptions. Nevertheless, because the study did not compare explicit and implicit SEL conditions, this interpretation remains a theoretically grounded hypothesis rather than a causal conclusion.

Teacher preparation and previous experience may constitute relevant conditions in this process. Intentionally integrating SEL into PBL requires teachers not only to organise group tasks but also to identify socio-emotional learning objectives, structure productive interaction, model relevant competencies, provide feedback on group processes, and design opportunities for reflection and transfer (Durlak et al., 2011). Similarly, research on collaborative learning indicates that placing students in groups does not in itself guarantee productive collaboration; teachers need to structure interaction, scaffold group processes, and monitor how students participate and learn together (Gillies, 2016). The teachers participating in this study reported that they had not received specific training in SEL or in its integration into PBL and had no prior experience with the systematic implementation of structured collaborative learning. Under these circumstances, teachers may understandably have focused primarily on curricular content, project management, and the completion of final products, while collaborative and socio-emotional processes remained less explicitly structured. However, teachers’ practices, knowledge, and implementation fidelity were not systematically assessed. Their limited prior training and experience should therefore be understood as relevant contextual information and a possible interpretation, not as an empirically demonstrated explanation for students’ results.

More broadly, previous research indicates that PBL should not be treated as a uniform pedagogical condition. Its outcomes are sensitive to variations in design and implementation, including the degree of instructional guidance, disciplinary alignment, collaborative structuring, reflection, feedback, and teacher support (Chen & Yang, 2019; Zhang & Ma, 2023). Consequently, the presence of projects labelled as PBL does not, by itself, ensure that all the cognitive, collaborative, and socio-emotional processes theoretically associated with the approach are systematically enacted.

The role of authenticity may also be considered from this perspective. Authenticity in PBL should not be reduced to addressing real-world topics or producing tangible and publicly shared outcomes. It may also require meaningful opportunities to apply disciplinary and socio-emotional competencies in situations that reflect the complexity of students’ lived experiences (Larmer et al., 2015; Sánchez-García & Reyes-de-Cózar, 2025). Such opportunities may involve regulating emotions under uncertainty, managing interpersonal disagreement, negotiating shared decisions, and considering the consequences of collective action (Blakemore & Mills, 2014; Steinberg, 2014). The limited changes observed in most competencies invite further investigation into the extent to which PBL designs facilitate the transfer of socio-emotional learning to authentic contexts. Nevertheless, because implementation fidelity and the degree of socio-emotional authenticity were not systematically assessed, the present study cannot determine whether these particular projects offered insufficiently authentic learning experiences or whether authenticity influenced the observed results.

In relation to RQ3, no statistically significant gender differences were detected in the magnitude of pre-test–post-test change for any of the five competencies. The available data therefore did not provide evidence that male and female students followed different patterns of change during the study period. However, this result should not be interpreted as demonstrating equivalence between the two groups. The comparisons for self-awareness and self-control yielded moderate effect-size estimates despite not reaching the conventional threshold for statistical significance. Given the small sample and the resulting uncertainty, larger studies are needed to determine whether gender-related differences exist in the development of particular self-perceived SEL competencies.

Regarding RQ4, the correlational analyses showed that the five self-perceived SEL competencies were positively associated at both measurement points. The pre-test and post-test correlation coefficients were consistent with the conceptualisation of SEL competencies as interrelated aspects of socio-emotional functioning rather than independent characteristics (CASEL, 2020). The findings therefore provide descriptive evidence that students who reported higher scores in one competency also tended to report higher scores in the others at both measurement points.

The cross-time correlations also indicated varying degrees of continuity in students’ relative scores, particularly for self-control, relationship skills, and responsible decision making.

Taken together, the findings suggest that the socio-emotional opportunities created by PBL should not be equated with systematic SEL instruction. Project work can create meaningful situations involving collaboration, regulation, negotiation, and decision making, but these opportunities may remain implicit unless they are translated into explicit objectives, guided practice, feedback, reflection, and assessment. The findings do not allow us to determine whether PBL does or does not contribute to the development of SEL. Instead, they question the assumption that measurable socio-emotional development can be expected to emerge automatically through participation in project work when SEL has not been intentionally incorporated into project design.

The main contribution of this exploratory study therefore lies in redirecting attention towards the pedagogical and contextual conditions under which PBL may support socio-emotional learning. Intentional SEL integration, teacher preparation, implementation quality, instructional scaffolding, and appropriate assessment may all be relevant conditions. However, their influence must be examined through comparative studies specifically designed to test these mechanisms. The present findings provide a basis for formulating such questions but cannot establish which conditions would produce different outcomes.

Practical Implications

These findings suggest several theoretically informed directions for educational practice. PBL designs could incorporate explicit SEL objectives alongside curricular goals and provide structured opportunities for modelling, guided practice, feedback, reflection, and performance-based assessment. Collaborative participation should not be treated as sufficient evidence that socio-emotional learning is taking place. Instead, teachers could identify which competencies students are expected to practise, how those competencies will be supported during project work, and what evidence will be used to assess their development.

Teacher training is particularly important for helping educators identify the socio-emotional demands embedded in project work and transform them into intentional learning opportunities. This preparation could include strategies for scaffolding collaboration, supporting self-control, facilitating conflict resolution, guiding responsible decision making, and assessing how students mobilise these competencies during project activities. These proposals should be regarded as theoretically informed directions for future intervention studies rather than as practices that have been shown to be effective in the present research.

6. Conclusions

This study found that students’ self-perceived SEL competencies showed limited variation following participation in four PBL experiences. Self-awareness, social awareness, relationship skills, and responsible decision making remained relatively stable across the two measurement points, whereas self-control showed a decrease. The positive associations observed among the competencies at both pre-test and post-test further support their interrelated nature, although they do not demonstrate that their internal structure remained unchanged.

However, rather than challenging the pedagogical potential of PBL, these findings invite reflection on the widespread assumption that socio-emotional development emerges automatically from collaboration and participation in project work.

The findings suggest that participation in project work alone may not necessarily translate into measurable gains in students’ self-perceived socio-emotional competencies. They highlight an important distinction between providing opportunities to use socio-emotional competencies and intentionally teaching them. PBL creates situations that require collaboration, regulation, negotiation, and shared decision making, but participation in these situations does not necessarily ensure systematic SEL development. When socio-emotional competencies are not translated into explicit objectives, guided practice, reflection, feedback, and assessment, their development cannot be assumed to emerge automatically through project participation.

The main contribution of this study lies in redirecting attention from whether PBL develops SEL to the conditions under which it may do so. Intentional SEL integration, teacher preparation, structured collaborative scaffolding, and performance-based assessment represent relevant directions for future research.

These pedagogical conditions should be tested through controlled studies before conclusions can be drawn about their contribution to socio-emotional development within PBL.

7. Limitations and Prospectives

The sample size constitutes a key limitation of this study, as the intervention was implemented with a relatively small group of students from a single educational context. This limits the generalisability of the findings and reduces statistical power, particularly for detecting small pre-test–post-test changes and gender-related differences. In addition, 18 students provided data at only one measurement point and were therefore excluded from the paired analyses. However, this limitation does not invalidate the study; rather, it positions the research as an exploratory case study that provides context-specific evidence on PBL and self-perceived socio-emotional learning in a real secondary education setting.

The pre-experimental design also constrains the interpretation of the findings. Although the participants belonged to two separate classroom groups, both classes participated in the same PBL condition and no comparison group was included. Consequently, the study cannot determine whether the limited variation observed in most competencies or the decrease in self-control was related to the PBL experiences, developmental processes, other events occurring during the academic year, or measurement variability. The self-control result should also be interpreted cautiously because it emerged from one of five separate pre-test–post-test comparisons, increasing the possibility of a Type I error.

The duration and instructional dosage of the projects may also constrain the interpretation of the results. Although four interdisciplinary PBL projects were implemented, socio-emotional learning may require sustained, explicit, and systematic instructional practices over time. Moreover, the presence of moderate-to-high baseline mean scores at pre-test suggests limited scope for detecting quantitative improvement, particularly using a self-report instrument. These findings reflect students’ perceptions of their competencies and do not establish how consistently they applied self-control, relationship skills, or responsible decision making in authentic situations.

A further limitation concerns teacher preparation and implementation. Participating teachers reported that they had not received specific training in SEL or its integration into PBL and had no prior experience with the systematic implementation of structured collaborative learning. This contextual factor may have shaped how collaborative and socio-emotional processes were supported. However, teachers’ knowledge and practices were not formally assessed, and no systematic observation protocol, implementation-fidelity measure, or fidelity checklist was used to examine consistency across teachers, subjects, projects, and classroom groups. The study therefore cannot determine whether or how teacher preparation or implementation conditions contributed to the observed results.

Finally, future research should aim to expand this line of inquiry by employing larger and more diverse samples, as well as comparative or quasi-experimental designs that include control groups, to strengthen causal inferences regarding the changes in PBL on socio-emotional development. Longitudinal approaches and interventions of greater duration and instructional dosage would also allow for a more accurate examination of how socio-emotional competencies evolve over time and under sustained pedagogical conditions.

Additionally, combining self-report measures with performance-based assessments, classroom observations, and qualitative data could provide a more comprehensive understanding of how students mobilise socio-emotional skills in authentic learning contexts.

Finally, future studies should place greater emphasis on documenting the pedagogical conditions under which socio-emotional gains emerge within PBL environments, including the potential role of explicit SEL objectives, scaffolding practices, reflective routines, teacher training and performance-based assessment.