Wooden Rainbow Blocks Stacking & Nesting Game | Creative Color Shape Matching Preschool Activity for Children Kids Boys Girls

 A rainbow Building block is a children's toy that consists of several arched pieces made of wood, in different sizes and colors, that can be stacked on top of each other to form a rainbow shape. The arches are usually flat on the bottom and curved on the top, with each arch fitting into the one below it, creating a stable structure.