A rainbow stacker is a Waldorf toy that is made of softwood and is gentle to touch. These colourful arches are mostly seen in the Montessori playrooms. The rainbow stacker is an open-ended toy that can be played with in various methods, they are best for children as they inspire imagination and creativity. In most cases, you will get an option of 6 or 12 wooden arches in a set that stack over each other from small to large. They are toys that can serve multiple purposes and are often used by kids for years to come. Your child will develop their fine motor skills, expand their creativity as well as learn about the various colours with a GrapplerTodd Rainbow Stacker.