Can you get out of it depends on the evidence. Since he is a juvenile he very well may get an informal adjustment, which is the juvenile version of a diversion and won't result in any true finding(juvenile of a conviction) which means it won't result in any juvenile history of true finding. You may want to consult an attorney to fully understand his options. Juvenile courts are usually fairly reasonable in matters like these.
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You will certainly need to retain local counsel to address this matter. Your counsel is going to want to evaluate two aspects of your son's situation: whether he would qualify for an informal resolution to this matter, and what the specific terms of your son's high school code of conduct are. Generally speaking, these types of offenses are usually not pursued aggressively; however, that will depend upon the specific circumstances of your son's case.