Collect foam, sponges, Styrofoam, etc. and cut them in various shapes. Fill the box and insert a challenge activity into the box. Secure with a rubber band. Create a number of different cards for the challenges but only place one card in the box at a time. Differentiate the task by limiting the number of shapes, used, adding curved shapes, working with a partner, taking turns, and adding one shape at a time, etc.