Attention Math Teachers: teach concepts like area, perimeter, symmetry, and congruence.! These 12 piece puzzles are perfect for teaching problem solving and patterning activities. Plastic pieces are scored in 1" sections so that visualizing area and perimeter is quick and easy. Set of 72 pieces. We meet at 3520 Rayford Road in the parking lot of HEB near the gas pumps (Grand Parkway and Rayford Road, NOT I45 & RAYFORD ROAD), cash only. For additional items for sale by us, click on the "more ads by this seller" link to the right of the picture.