Every year boys and girls go to Boy Scout camp, Day camps, Girl's Camp, church camps, sports camps, etc. and every year there are kids of a variety of ages that get home sick and want to go home. What they are having trouble with is the change in routine and predictability. What is a parent to do? Do you go get them or make them tough it out?
1. Parents know which children have more of a difficulty in dealing with unfamiliar situations and people. For some it is a matter of concern and for others it secretly is a matter of assurance that they are still wanted and needed by their child. Keep your eye on the ball here. The goal is to develop confident, self directed individuals. You don't want your child to be unable to go to school, to work, to college, or to leave home to get married.
2. Think of it as a journey. Don't wait for the "big event." Build up to it. Sleep overs with friends. Going to movies or the mall without parents. Taking swimming lessons. Baby sitting for other people. All of these help children to gain confidence and independence.
3. If you are already in the situation with a child (the event is here) then provide a lifeline. The child can call home once each day to report on what they are doing and the call lasts only 5 minutes.
4. If the child is new then assign them a buddy from the start so they have someone to do things with.
5. If you are a leader it may seem harsh, but let them know they can sit and put (cry or whatever) or they can have fun with the others. Be aware of safety issues as there are cases where children have made the decision to walk home.
6. When talking with the child (as the parent or as the leader) don't focus on the homesickness, wanting the parent or things like that. Watch the words you use. (I have had many parents of preschool age children that have conversations like this with their child. "I am leaving now, are you going to be all right. I will be gone for a long time and you won't see me. You will be here with only your teacher. Are you sure you are all right." Then when the child gets upset, the parent says, "see he has a hard time and maybe I should stick around or maybe he is too young."
7. This is not a maturity issues and giving the child another year (whether he or she is 3 or 13 will not make a difference. It is a learned and reinforced behavior built on child temperament and tendencies.