EFFECTS OF PROBLEM BASED LEARNING APPROACH ON SECONDARY SCHOOL STUDENTS’ MOTIVATION TO LEARN PHYSICS IN ISIOLO COUNTY, KENYA. INTERNATIONAL JOURNAL OF ADVANCED RESEARCH AND REVIEW (IJARR), [S. l.], v. 8, n. 7, p. 13–24, 2023. Disponível em: https://www.ijarr.org/index.php/ijarr/article/view/421.. Acesso em: 25 jun. 2026.