12 months & up. With multiple ways to play, children will enjoy this hands-on practice as they build their STEM skills matching colors, stacking, patterning, and counting. These easy to grip stackers are sized perfectly for smaller hands. Encourage children to stack their pieces high or come up with their own patterns. Have children practice counting as they stack the brightly colored stackers. This set comes with three unique stacking cups of each of the primary colors.