He will appear in juvenile court. If he was arrested by the police, you should have received information relative to his next steps. For a $50 item, I doubt the juvenile court will bind him over to an adult court for trial.
If he detained by store security, and the police were not involved, you'll likely receive a letter demanding you to pay tribute to the merchant. If you pay the tribute, the entire matter is wiped away.
If the police were involved, you've received (or will soon receive) instructions to be followed. If you wish, it can't hurt to consult a criminal defense matter. If he goes to Juvie court, he'll be ordered to take a class (or two) on ethics, honesty, stealing, etc... He might be ordered to write a paper on being a good citizen, do community service, pay a small fine, and probation. In the end, if he does as instructed,this will all be wiped away. But, he's innocent until proven guilty. So, shutting up, waiting, staying out of trouble, going to school will serve him well.
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