Base 10 Class Set includes 600 unit cubes, 200 ten rods, 20 hundred flats, 3 thousand blocks and 50 base ten activity mats in a durable storage container. Base 10 Small Group Set includes 100 unit cubes, 10 ten rods, 10 hundred flats and 1 thousand block. Base 10 Write-on/Wipe-off 2-Sided Mats are 9" x 12" mats of hundreds, tens and ones. One side shows blocks and the other a labeled grid. Each side has space for student to write in numbers with dry-erase markers.