Early in the 20th century, Dr. Maria Montessori, Italy’s first woman physician, developed educational materials and methods to prepare an environment for learning based on her belief that children learn best by doing, not passively accepting other people’s ideas and pre-existing knowledge. This idea of learning by the active personal pursuit of many different experiences: physical, social, emotional, and cognitive, was an innovative concept at the time and remains valid today, one hundred  years after its inception.  Dr. Montessori further believed learning should occur in multi-age classrooms where children at various stages of development learn from and with each other. Her fundamentally appropriate approach was designed to fit each child instead of making each child fit the program.