Organize By Group Color With Sturdy Tubs. These open-topped tubs are sturdy enough for the most lively classrooms. With two tubs in each of the four grouping colors, they’re perfect for storing group materials or organizing small group work.. This 8 pcs. set comes in an assortment of bright colors including red, green, yellow and blue. 15.75″ x 6.5″ x 6″ (8 pcs. per set) Plastic. Stacks for easy storage. Accessories not included.