Synthetic biology’s focus on creative bio-design processes and real-world applications makes it a promising field for educational interventions aimed at addressing the “leaky pipeline” issue, where students drop out of the pathway from high school to post-secondary education and careers in science, technology, engineering, and math (STEM) fields. The COVID-19 pandemic has renewed calls to improve student retention in the STEM pipeline by providing access to high-quality, equitable STEM education opportunities both inside and outside of school. The pandemic underscored the importance of scientific advancement and a robust STEM workforce while exposing the education system’s struggle to recover lost ground (White House, 2022). Recent educational initiatives, including those by the U.S. Department of Education, seek to address various factors—both cognitive and non-cognitive—that influence students’ decisions to remain in STEM pathways at critical stages of their education (Marten, 2022; U.S. Department of Education, 2023).

Many students who initially express an interest in pursuing STEM careers lose that intention during high school. For example, a longitudinal study of over 24,000 high school students revealed a 48% decrease in those intending to pursue STEM careers between 9th and 11th grade (Mangu et al., 2015). Since students’ post-secondary STEM choices are closely tied to their high school science experiences and self-perceptions, educational interventions that provide meaningful science experiences and foster positive self-perceptions may enhance retention and equity within the STEM pipeline (Wang, 2013; National Science Board and National Science Foundation, 2021).

Career trajectories in STEM fields and the factors influencing related decisions are complex and dynamic. However, students with positive self-perceptions related to science—those who identify as a “science person”—are more likely to persist in STEM pathways (Metcalf, 2010; Vincent-Ruz and Schunn, 2018; Chen et al., 2021). Science identity, particularly among underrepresented student populations in STEM, is one of the strongest predictors of persistence in studying STEM subjects throughout high school and college, as well as commitment to a STEM career (Aschbacher et al., 2010; Barton et al., 2013; Chemers et al., 2011; Le et al., 2014). Understanding how educational interventions can promote science identity is crucial for educators, policymakers, and STEM professionals to positively impact students’ self-perceptions and, ultimately, their persistence in STEM pathways.

In human development, identity refers to an individual’s “sense of self,” which is shaped by their participation in specific activities, societal roles, group affiliations, interests, and personal characteristics (Burke and Stets, 2009; Renninger, 2009). Science identity, being both social and contextual, involves a student’s self-perception of “who they are, what they believe they are capable of, and what they want to do and become with regard to science” (Brickhouse, 2001; Kim et al., 2018). According to the model described by Carlone and Johnson (2007), science identity comprises three dimensions: competence, performance, and recognition. Competence refers to possessing and understanding scientific knowledge and methods; performance involves demonstrating this competence to others; and recognition involves being acknowledged as a “science person” by oneself and by peers and significant others. Educational interventions that foster a sense of community and affiliation, promote positive attitudes, and align school science activities with authentic scientific practices have been shown to enhance science identity among adolescents (Vincent-Ruz and Schunn, 2018). A strong science identity can empower students to view themselves as active and valued contributors to science, rather than passive learners.

One strategy that has shown some promise for increasing students’ science identity is Project-based learning (PBL). PBL is an educational strategy that holds significant potential for enhancing science identity and increasing STEM retention, particularly among underrepresented groups. PBL emphasizes collaborative, student-centered learning through projects that are meaningful, relevant, and connected to real-world challenges. Research has shown that PBL fosters deeper engagement, improves problem-solving skills, and cultivates a sense of ownership over learning (Krajcik and Shin, 2014; Mergendoller and Thomas, 2013). Among underrepresented groups, PBL can provide a culturally responsive approach to STEM education by incorporating students’ lived experiences and interests into the learning process, thereby enhancing their sense of belonging and self-efficacy in science (Barton et al., 2013; Ladson-Billings, 1995). Additionally, PBL supports the development of science identity by allowing students to see themselves as active participants in the scientific process, gaining recognition for their contributions and developing confidence in their scientific abilities (Chin and Osborne, 2008; Moote et al., 2020).

Building on these general benefits of PBL, synthetic biology and biotechnology education provide fertile ground for applying PBL principles, offering authentic, interdisciplinary challenges that can further enhance science identity and engagement. Synthetic biology offers unique opportunities for educational interventions aimed at fostering science identity, while also benefiting from the increased diversity and strength of a more robust STEM pipeline. Educational interventions in synthetic biology often involve interdisciplinary projects that challenge students to tackle real-world problems from diverse contexts and to evaluate or create biological solutions using engineering design thinking (iGEM Foundation, 2024; NISE Network, 2024). These interventions, which integrate life sciences with the engineering design-build-test-learn cycle, highlight creativity, innovation, real-world relevance, and authenticity—factors that are known to enhance science identity and increase student persistence in STEM fields (Shanahan and Nieswandt, 2009; Vincent-Ruz and Schunn, 2018). Engaging high school students in authentic, original research has been linked to increased research identity, motivation, and a higher likelihood of pursuing and sustaining a career in STEM, compared to students who do not engage in original research until college (Deemer et al., 2022). Synthetic biology research interventions at the secondary education level may be especially crucial in addressing the “leaky pipeline,” as they infuse science education with elements that promote science identity at a critical juncture for STEM student retention (Graham et al., 2013). Walker (2021) conducted a survey of 66 middle school students, followed by interviews, to explore what this age group knows and thinks about synthetic biology and modern biotechnology applications. The study found that while students had minimal knowledge in these areas, their attitudes were similar to those of high school students, suggesting that these attitudes can be shaped during their remaining years of schooling. Walker also highlighted the need for further research to support student learning throughout their educational journey, emphasizing the importance of developing a strong pipeline to meet the growing demand in these fields. Additionally, Walker’s analysis of prior research indicates that factors such as age, science learning experiences, and the geopolitical landscape significantly influence students’ knowledge of and interest in biotechnology.

In light of Walker (2021) findings, there is a need for additional research on effective instructional formats for teaching synthetic biology content. Project-based science interventions introduced at earlier educational stages may be beneficial, but research is required to assess their overall effectiveness. One such project-based science intervention is the BioBuilderClub, an extracurricular program offered by the BioBuilder Educational Foundation, which emphasizes authenticity in synthetic biology education. The BioBuilderClub engages high school students worldwide in experiential learning, allowing them to tackle real-world challenges with local or global significance. Students work virtually with a practicing bioengineer mentor as they design biological solutions using the design-build-test-learn engineering cycle. While some teams advance to the build and test phases, the BioBuilderClub season culminates in a celebration of student achievements. Here, all teams have the opportunity to present their bio-design processes and research findings through various formats, including oral reports, poster presentations, written abstracts, and publication in peer-reviewed journals.

Prior to the study, institutional review board approval was obtained. The following study used multiple methods to assess the effectiveness of the project-based science education intervention. Specifically, we used a quasi-experimental one-group pre-posttest design to assess students’ engagement, competency, and content knowledge before and after the project-based science program. We explored the factor structure and internal consistency of our developed survey on scientific self-beliefs, and we assessed the interrater reliability of the developed rubric of understanding synthetic biology.

Since 2015, over 1,500 students from diverse schools in 22 states have participated in BioBuilderClub. In the 2023–2024 school year, there were a total of 285 students who participated in the BioBuilderClub. From that participation in the 2023–2024 school year, we used a convenience sampling method and included students enrolled to participate in the project-based science program. Both consent by parents and assent from high school students were obtained during the registration process prior to participation in the program. Students were recruited by BiobuilderClub (i.e., program coordinator, instructors) to complete the pre-survey and post-survey online. To maintain anonymity, surveys were de-identified by BioBuilderClub prior to being shared with external evaluators. Students were incentivized to complete the post-survey by entering students into a raffle for an Amazon Gift Card if they completed the post-survey. There were 246 students (86.3%) who completed the pre-survey and 137 students (48.1%) completed the post-survey. However, there were only 124 students (43.5%) who had completed both the pre and post-survey (see Table 1 for participation rates and demographic information).

For the 2023–2024 school year, there were 286 students enrolled in the project-based science program. Of that total 286, 246 individuals responded to the pre-survey and 137 individuals responded to the post-survey. Of the 137 students, there was a higher response rate for the same individuals who completed both the pre-and post-survey (n = 124). For the frequency of demographics across pre and post survey results in the 2023–2024 School Year (see Table 1).

The findings of this study highlight significant positive outcomes for students participating in the project-based science education intervention, filling a critical gap in the existing literature regarding the effectiveness of such interventions in enhancing students’ science identity, self-beliefs, and content knowledge. Previous studies have emphasized the importance of fostering science identity as a key factor in retaining students in STEM pathways (Aschbacher et al., 2010; Barton et al., 2013; Chemers et al., 2011). This study contributes to that body of knowledge by demonstrating that participation in a project-based intervention like BioBuilderClub not only increases students’ scientific engagement, competency, and content knowledge but also enhances their interest in biotechnology and related fields, aligning with the findings of prior research on the importance of authentic, hands-on learning experiences (Deemer et al., 2022; Shanahan and Nieswandt, 2009).

Our examination of high school students’ self-beliefs regarding their scientific engagement, competency, and content knowledge revealed that students who participated in the intervention during the 2023–2024 school year demonstrated significant increases across these areas. This outcome is consistent with the theoretical framework suggesting that students who view themselves as competent and engaged in science are more likely to persist in STEM pathways (Carlone and Johnson, 2007; Vincent-Ruz and Schunn, 2018). The evidence of a three-factor structure in our exploratory factor analysis (Table 4; Figure 8) supports the construct validity of these measures, with internal consistency values (α = 0.79–0.91) further confirming the reliability of our findings.

Increased scientific engagement was particularly noteworthy, as students reported greater involvement in scientific activities beyond the classroom, such as engaging with science during weekends and school breaks. This finding suggests that the project-based science education intervention successfully fosters a deeper interest in science, consistent with literature highlighting the importance of sustained engagement for the development of science identity (Metcalf, 2010; Vincent-Ruz and Schunn, 2018). Additionally, students demonstrated improved scientific competency, including their ability to understand scientific information, generate problem-solving methods, and conduct independent investigations—skills that are critical for future scientific endeavors and align with the competencies described by Carlone and Johnson (2007).

The program also effectively enhanced students’ content knowledge in synthetic biology, a field with growing importance in the modern bioeconomy (Graham et al., 2013). Students showed significant gains in understanding key concepts and techniques, such as reading primary scientific literature, writing research proposals, and presenting scientific ideas. This improvement was corroborated by both quantitative measures and qualitative feedback from students, who expressed confidence in their newfound knowledge and skills. These outcomes address the gaps identified by Walker (2021) and others who have called for more research on how to effectively teach synthetic biology and related fields at earlier educational stages.

Students overwhelmingly recommended the project-based science education intervention, noting that it provided valuable educational experiences. They particularly appreciated the opportunity to collaborate with peers and mentors, learn in a supportive environment, and engage in creative scientific projects. The program’s emphasis on hands-on, practical learning experiences, which has been highlighted as a key factor in successful STEM education (Shanahan and Nieswandt, 2009; Vincent-Ruz and Schunn, 2018), was a critical element of its success.

In addition to the benefits for students, the program aimed to raise awareness of biomanufacturing and modern life sciences among community stakeholders. Engaging parents, teachers, college admissions officers, and relevant businesses is crucial for creating a supportive ecosystem for students pursuing careers in biotechnology, as noted in previous studies (Marten, 2022; U.S. Department of Education, 2023). The program’s efforts to communicate and celebrate student achievements publicly helped build a positive perception of biotechnology as a viable and rewarding career path.

However, while students demonstrated increases in engagement, competency, and content knowledge, the residual change regressions for each item (n = 103) did not reveal significant differences by gender, locale, or first-generation status. This finding suggests that the intervention was broadly effective across different demographic groups, but it also indicates a need for future research to explore potential differences in outcomes among more diverse student populations, particularly those systematically excluded from STEM fields (Aschbacher et al., 2010; Barton et al., 2013).

For knowledge of synthetic biology, our raters found that students who participated in the intervention demonstrated increased understanding of synthetic biology (see Figures 13, 14). These findings are consistent with the literature on the importance of providing authentic, interdisciplinary science experiences that connect students with real-world problems and solutions (iGEM Foundation, 2024; NISE Network, 2024).