These mats have base ten blocks (hundreds, tens, ones) pictured on one side. On the reverse is a grid with labels "hundreds," "tens" and "ones". Each side has space for students to write in numbers. Mats measure 9" x 12" and are made of tough, flexible plastic for use with dry-erase markers. Set of 10 mats. Grades 1-6. Set of 10 mats. Write-On Wipe-Off Surface. Perfect for practicing base ten concepts. Reusable. Age: 6-12 years/Grade 1-6