Classroom organization across age groups
Create a classroom for each room in your program with its own name, capacity, and age range in months. Children are assigned to a classroom, so rosters build themselves and moving a child up an age group is a single change rather than an edit in four places.
Teachers are assigned to classrooms too, so each room has a clear staff list. Directors can see every classroom side by side — how many children are enrolled against capacity, and who is assigned to teach them.