Our product is a block to make a playground. It is made of special structure proven by various experiments, so children can made it. You can build almost everything you can imagine with just the basic unit blocks. As well as connecting up and down, it can expanding to the side. It is possible to create organically and freely like cells make organs. This will help to develope children's creativity and thinking power, and will contribute greatly to the accumulation of architectural experience and knowledge that can be said to be a composite of art and science in modern society. In addition, the worth that children have after they have seen their buildings or things can make them to experience a new feeling like when they were toddlers.