In ohio, it is unlawful to provide or sell a handgun to anyone under 21, and they are not permitted to possess one unless it is during legitimate educational or sporting purpose. So I can provide one to someone under 21 to teach them or for plinking (while I'm there supervising), but I cannot give one to them for protection in their home.
A lot of states have similar conditional laws like this, which, if I'm not mistaken, are simply a legible version of the federal law.