The role of teachers in using these theories in their work is to design and plan their curriculum to stimulate children's learning and cognitive development through play. Educators act as stage managers. They are required to schedule some time for children to participate in open-ended, self-initiated free play. They must set up environments for play, planning times with sufficient space, materials and time for children to play. For example, an early childhood teacher decided to have children play with sand in one day. She/He must set up the sandpit in a safe area and fully supervise the children to ensure they play safely. She/He must provide a sufficient supply of tools and materials to use in the sand so that each child has adequate choices to choose the tools he/she wants. Rather than dividing the tools for the children, the educator lets the children make their own choices and thus the children can gain some sense of control. When children play with sand, the educator should carefully observe each child, encouraging them to solve problems on their own and consider their own feelings (Crosser, n.d.). Furthermore, the educator should interact with children in a responsive and positive manner. She/He can ask questions including: “What do you think/feel about the game?