The arrangement of our Classrooms The Nest Class consists of children aged 4 months to 12 months. The adult to child ration is 1:4 in the Nest class. The Nursery Classes care for children aged 12 months to 3 years of age. We have two Nursery classes each with an adult to child ration of 1:7. The Preschool classes consist of children aged 3 to 6 years who are taught by trained Montessori teachers per class. We have 3 Preschool classes each with an adult to child ration of 1:12.