This Base 10 Grid Lapboard is perfect for the classroom, home and even travel. One side of the sturdy melamine whiteboard features two Base 10 squares for teaching addition and subtraction as well as other math activities and lessons. Plain\/blank surface on back can be used for teaching multiple activities and lessons. Dry-erase surface erases cleanly and easily. Lapboard is great for interactive instruction to test concept understanding or work with small groups.