Montessori classrooms are based on 3 year family groupings, in keeping with Dr. Montessori’s Planes of Development.
| Development | Approx. Ages | Classes | Associated Grades |
| Plane 1 | Birth – 1 ½ | Parent/Infant Classes | |
| 1 ½ – 3 | Toddler Community | ||
| 3 – 6 | Casa dei Bambini | Preschool and Kindergarten | |
| Plane 2 | 6 – 9 | Lower Elementary | 1 – 3 |
| 9 – 12 | Upper Elementary | 4 – 6 | |
| Plane 3 | 12 – 15 | Erdkinder | 7 – 9 |
| 15 – 18 | High School | 10 – 12 |