Setting up Family Sharing/Apple ID without using school email I am trying to set up Find My iPhone on an Apple 5s for my 16 year old son.  However, he does not want his email address used for the Apple ID because it is connected to his school.  Would there be any drawback to setting him up as an "under 13" child so he doesn't have to use his school email?
Why would you do this? When creating an Apple ID you are also creating an iCloud account. Just use the iCloud email generated as part of the process, or create a new email address for this purpose using any other free email service of your choice such as Gmail. (If you state he is underage, Apple will force you to use the iCloud email and will not allow you to use a non-Apple email for the account.)