As you conduct your phone interviews you may have the occasion to talk with a director of a program with a specific educational philosophy. Those educational philosophies will likely fall under one of 4 philosophies.
Montessori - This approach, developed by Maria Montessori in Rome in the early 1900s, is child-centered, with teachers serving as guides. In the Montessori program model, play is a child's work. While there is a focus on academics, the distinguishing feature is that children learn at their own pace. There are special Montessori toys called manipulative's that are self-corrective; this means that a child knows if they assembled a puzzle correctly, for example, based on the toy fitting together, not because someone showed the child how to do it.
That focus on letting children learn at their own pace also affects how classrooms are arranged, with children ages three, four and five all being in the same room. This allows the older children to serve as role models for the younger ones, and also exposes children to different ages. Children generally have the same teacher for those three years, allowing close teacher-student relationships to develop. The mixed-age aspect also encourages older children to help the younger children, which helps build their self-esteem.
Waldorf - This play-based approach is characterized by a predictable structure, providing children with a dependable routine, such as certain days of the week for set activities like baking or gardening, as well as mixed-age classrooms with the same teacher for multiple years. There is an emphasis on creative learning, reading, singing, acting etc. There is also an emphasis on cooperation, and the setting generally appears like a home—warm and friendly, with wooden toys and natural materials.
What stands out about Waldorf is its stance against traditional grading systems and exclusion of media in the curriculum. Waldorf does not include media (computers, videos or electronics of any kind) and also does not involve academics, which means no homework, tests, handouts or even desks. Children are introduced to formal reading skills in the first grade. The programs are "all-weather" and children spend a lot of time outdoors.
High Scope - This curriculum, which can be found in a lot of community-based programs, such as the local church or YMCA, revolves around a concept of active participatory learning, holding that "children learn best through hands-on experiences with people, materials, events, and ideas."
Bank Street - The Bank Street philosophy was developed by the Bank Street College in New York City and is very similar to play-based learning. The program hold a child-centered philosophy and believe that children are "active learners, explorers, experimenters and artists" and benefit from a diverse curriculum.
The philosophy stresses the importance of materials in the classroom and views the teacher as a "facilitator of learning." This method aims to help children make sense of the world around them by studying multiple aspects of their environment.
It's less important whether the school touts a particular educational philosophy or curriculum style, and much more important that the director and teachers feel excited and enthusiastic about what they do.