Summary Give students a series of challenges, some individual some requiring teamwork. Science content Physics: Motion and Forces, Newton’s Laws, Gravity (K, 2, 6) Activities in this lesson Cup tower challenge Paper tower challenge Bridge building challenge Procedure Do each challenge in turn. I also added in a pulley challenge: students were given two pulleys and a long length of rope, and asked to make a pulley system to move a bag from one end of an area to another. They worked together, with help from me, to understand how a simple pulley works. Grades taught Gr 4 Gr 5