This is the important bit that people miss. Google isn't allowed to warn you that changing your age will apply restrictions to your account, and they aren't allowed to let you easily undo it after it's done. This is what happens when Congress dictates user interfaces.
So, in effect, this means a kid is 13 as soon as he figures out he needs to be 13. OK.
Not all kids are created equal, and some kids will be 13 sooner than others. Some might argue that's not fair. But, back in the day, I would not have been among them.
