Dr. Maria Montessori founded the Association Montessori Internationale in 1929 to preserve her legacy. AMI ensures that Montessori schools and teachers are both well-grounded in the basic principles of the method and ready to carry those principles forward in the modern educational world. AMI offers teacher training and conferences, approves the production of Montessori materials and books, and, through their AMI-USA branch office, accredits schools. American Montessori Schools are also accredited by the American Montessori Society (AMS), and many teachers and teacher training programs are also certified by AMS. ALL teachers at OKCHMS have a Master's degree in Montessori education, and are certified by AMS.