• cinder blocks to use as weights (or a stack of uniform textbooks)

Each group needs:

• piece of wood (a smooth flat object to put the cinder blocks on)
• 4 3" x 5" index cards
• 8.5" x 11" copier paper
• 8.5" x 11" plastic transparency
• 12" masking tape
• (optional) 15 toothpicks
• (optional) 2 drinking straws
• ruler
• scissors
• 4 pairs safety glasses