if youre under 18 and enter into any contract, you can exit that contract at any time before you turn 18 (and a reasonable period of time afterwards). a contract is anything like buying a TV from someone, buying a car from a dealership, agreeing to mow someones lawn each week for $50, buying a box of pencils from your neighbor, buying cake from a bakery, ect. the only caveat here is that when you cancel the contract, you have to return what ever you got in the contract
at the time you decide to cancel the contract.
example: youre under 18, you go to best buy and buy a playstation on your own accord. you go home, and a week later you spill water all over the playstation and completely ruin it, doesnt even turn on. you decide you want to return it (you didnt get any sort of warranty through best buy that would cover this otherwise), so you take it back to best buy. your entitled to being able to exit that contract, aka get a full refund if you just give them back that broken ps4.
if two minors enter into a contract, either minor can cancel the contract at anytime before they turn 18.
an exception to this rule is for things that are deemed necessary for a minor to live, things like food, shelter, ect. so you cant go to mcdonalds, order a #9, eat half, then return half a burger. you could get away with like, buying gum from a gas station, chewing up every piece, then returning the chewed up gum and getting all your money back.
this law even applies if you lie about your age, so if you buy alcohol with a fake ID, you can go back and return the empty alcohol bottles and youre entitled to a full refund. you can, in this case, still be charged criminally for illegally buying alcohol. i think this might be more of a gray area, because p sure theres cases where they say if you go to great lengths to obscure your age, you can still be held liable to the contract as a non-minor.
a couple sources, i learned this in my law class and looked into it some more. there might be other exceptions to the rule that im missing:
https://contracts.uslegal.com/contract-by-a-minor/https://www.hg.org/article.asp?id=34024TL;DR if you're under 18 and bought something you no longer want, and have proof that it was you that bought it, you can return it no matter what state its in (probably) and get a full refund.