We have planned a workshop program for the "Exhibition of things around me" in Chigasaki Museum. We developed the "Mammoon" toy with the cooperation of Babot, Inc. to fit the theme of the exhibition. Mammoon is a wearable toy made with balloons. It inflates with a small battery operated fan. Children can go inside and walk around wearing the toy. The parts on the outside of the toy can also be decorated. Add on the parts and suck up the air inside to shape the toy and give it a mysterious character. Children can transform into whatever they choose by becoming one with Mammoon. This program allows children to experience the exhibition's theme of "things around me" by playing with air, something that normally goes unnoticed.