This study focused on misconceptions related to light and vision. Researchers administered diagnostic tests about light, vision, and color before and after instruction to 227 fifth-grade students over a 2-year period. They also conducted 11 clinical interviews. The tests and interviews revealed that almost all students shared certain misconceptions about light and its role in vision. In particular, most students believed that their eyes perceived objects directly rather than detecting light reflected by those objects. Most students also viewed color as a property of objects, not of light reflected by those objects. When teachers used conventional textbook-based methods of instruction, only a few students were successful in changing these misconceptions. Most students, however, successfully mastered the scientific conceptions when teachers used materials specifically designed to help students overcome their misconceptions. (Author/ML)