The magnetic way to demonstrate numbers and operations! Large 2" magnetic discs provide whole group demonstration developing number sense. Color_coded according to place value, the magnetic foam discs allow teachers (or students) to demonstrate on any magnetic board while students visually track what happens when numbers regroup in both addition and subtraction. And they help illustrate that multiplication is the same as repeated addition, and division the same as repeated subtraction. Set of 80 includes 20 each ones, tens, hundreds, thousands.