Shake up addition practice with hands-on number boxes students can’t resist! Our self-contained boxes make it easy for students to visualize numbers and quantities—and master basic addition, too. Children just shake them up and watch where the balls fall—for a concrete representation of the different ways to build and add each number! You get a set of 10 durable plastic number boxes representing sums 1-10; with a guide. Each box measures 2 3/4" x 4 1/2".