THE EFFECTS OF SCHOENFELD PROBLEM-SOLVING  INSTRUCTIONAL  STRATEGY ON PERFORMANCE  OF  SENIOR  SECONDARY II  STUDENTS  IN  MATHEMATICS IN GOMBE STATE, NIGERIA. DMJN. Published online April 24, 2025. Accessed February 5, 2026. https://gagdm.com/index.php/DELSULIBRARYNIGERIA/article/view/155