The early childhood environment is often called the second teacher. Its importance to the development and learning of the young child is critical. It includes indoor furniture, outdoor play equipment, and educational materials of all kinds for both the indoors and outdoors, arranged in centers and clusters to encourage certain kinds of activities, including play. It also includes books for children to look at and read (including a variety of art books), and for adults to read to students. All these materials and books must be carefully selected with the developmental age of the students in mind, and using the program’s curriculum as an overall guide.