Before and after school isnt' so much about the length of time but is about the cost of supplies used by the children. A child in care for an hour still gets an after school snack so costs the same to care for as one there two hours. Again it is a space issue since the child is using one of your spaces so even though they are only there a short time you can't give the extra hours to anyone else. When you look at it as they are booking a block of time in your daycare and using as much of it as they want then you should feel better. At the same time if this same family for any reason needed the child to stay longer on a night but before your final closing time I probably would not be charging them any additional fees with the idea thay are paid up from 3:30 - 5.