Theories give us insight into how children develop. There are seven major theories of child development, and each one is useful in understanding children’s needs at a given age. It is important that teachers have a deep knowledge of children in order to create learning experiences that support development. High-quality early childhood programs must be informed by theory. There are a variety of approaches and philosophies in early childhood program models, and each has its own unique benefits. One thing that all program models have in common is the connection to theory that supports children’s optimal development.