Playskool Dry-Erase Board Double-Sided Learning Mat - Skill Set: Addition The erasable, educational learning mat from Playskool - Addition. Features Mr. Potato Head and makes learning fun! Perfect for teaching and practicing basic skills - Skill level: preschool, kindergarten, 1st grade Great for learning at home or as a teaching aid in the classroom. Works with any brand of dry-erase markers or crayons (sold seperately) There are 4 different learning mats available in this series: Telling Time, Addition, Letters, Subtraction (each sold seperately) Large Size: 11 in X 17 in - Ages 4+