The document outlines a science lesson redesign for a Grade 9 class on momentum and impulse. The lesson objectives are to relate impulse to momentum, describe different types of collisions, and infer how momentum is conserved before and after collisions. The learners are regular Grade 9 students who have difficulty with physics problems. The lesson is being redesigned because momentum and impulse was one of the least mastered skills, it provides common ground for group work, and to help students understand the practical significance to road safety.