Linking Chemistry Learning to Careers: Impact of Career-Based Differentiated Instruction (CBDI) on STEM Students’ Self-Efficacy and Outcome Expectations

Despite efforts to achieve Sustainable Development Goal (SDG) Target 4.4, which seeks to increase the number of youth and adults with vocational skills for employment, STEM education in the Philippines continues to face gaps in career relevance that link classroom learning with workforce needs. This study aimed to develop and validate a career-based differentiated instruction (CBDI) resource package in General Chemistry 1 for teachers and evaluate its impact on STEM students’ self-efficacy and outcome expectations. The development phase entailed applying chemistry concepts to fields in engineering, technology, and health. Experts affirmed the relevance of CBDI in these career fields. The implementation phase used a quasi-experimental design with 161 grade 12 STEM students using pre- and post-tests through Career Decision Self-Efficacy (CDSE) and Vocational Outcome Expectations (VOE) scales. Paired samples t -test showed no significant changes in the control group, while the experimental group achieved significant improvements in self-efficacy [ t (84) = −9.30, p < 0.001] and outcome expectations [ t (84) = −5.95, p < 0.001] after eight (8) weeks of intervention. Independent samples t -test confirmed significantly greater gains for the experimental group in self-efficacy [ t (155) = −5.26, p < 0.001] and outcome expectations [ t (158) = −4.08, p < 0.001]. Reflexive thematic analysis from classroom observations and student reflections further supported these results, highlighting career-based laboratory experiments, collaborative activities, problem-solving, and case studies as mechanisms of improvement. The study concludes that the developed CBDI resource package is valid and that its implementation significantly improved students’ self-efficacy and outcome expectations. It recommends classroom adoption, school integration, and policy-driven pilot implementation.