You could use something like Tasker or Setting Profiles for that, but you can also use SeekDroid which will let you locate the phone in a web browser and set up fences (so you get notified if the phone leaves or enters an area). You can even hide the app and set a password on it so it can't be disabled.
It also had some other cool stuff...like if the phone is lost or stolen you can send a message to it, sound an alarm, lock it, change or set the paradise, and even wipe it.
I don't know off hand if the fences feature requires the paid membership or not though.
There's another app called Cerberus that has similar features.
I think it's a good idea to have one of these installed anyways, just for the peace of mind of having it if the phone is lost or stolen or if you need to locate your kid.