2 years & up. With these Sorting Stones children can explore colors, shapes, and patterns. The durable 1.5" diameter stones have a colorful bug character engraved on one side. Each set includes 20 stones, with five bug body shapes: circle, square, rectangle, triangle, hexagon and in four colors: red, blue, yellow and green. Great for indoor and outdoor play. An activity guide is included with ideas on how to introduce the stones to your setting, plus games exploring sorting, counting, and pattern skills.