Nimano-Sato, a home for the mentally handicapped has four viewpoints to guarantee their development, that is, Life, Education, Labor and Medical service. But we do not clarify the mutual relation among the four viewpoints. We want to try making clear the construction. In such a trial it is necessary to have common understanding of each definition of these terms. With this intention we study the meaning of labor in relation to play as a first step. They consider play and labor as a coodinate concept in contemporary Japan. School education locate play and studying alternatively according to child's ability. But the materialistic view grasp the meaning of each concept in a coomon purpose. It is important to adhere to such a standpoint in approaching the quetion how to guarantee their labor and development.