Smart Poly™ material has been designed for the classroom and home. The material is strong, durable, water resistant, and does not need lamination. Practice subtraction with this learning mat. Includes tables 1-12. Heavy duty double-sided surface for fun and colorful learning on both sides. Write-on/wipe-off surface. Use with dry erase or water based markers and washable crayons. Each side is an interactive lesson. Mat measures 12" x 17" .