These easy-to-manipulate discs provide hands-on practice for developing number sense. Color-coded according to place value, the foam discs allow students to visually track what happens when they regroup numbers in both addition and subtraction. And they help illustrate that multiplication is the same as repeated addition, and division the same as repeated subtraction. Packaged in re-sealable poly bag for easy storage. Discs are 1 inch in diameter, 1/8 inch thick, and made of EVA foam for easy manipulation and quiet classroom activity. 25 each of 4 values: one, ten, hundred, thousand. 100 total discs in set.