Does anyone know of any places that will let me cash a personal check that my grandma wrote to me?

You have to take it to the bank that is named on the check, and these days they will probably try to charge you to cash it. Then you have to complain to your grandma and she has to threaten the manager and it really is not worth the effort. Best way is to deposit the check into your parent's account. Second best is to ask your grandma to send you a postal money order which you can cash at the post office.