Teach multiplication right on the whiteboard with these jumbo math tools — big enough for the whole class to see. A great tool for teaching multiplication as repeated addition and division as repeated subtraction. Includes 2 magnetic 5x5 arrays, 50 discs and an Activity Guide. Arrays measure 9.75 x 9.75 in. Size: 28.7 x 26.7 x 4.1 cm. Ages 7+.