It depends on your state. In many states,15-year-olds can get a work permit that allows them to get a part-time job. It's usually a simple form that your school administrators and employer will have to sign.
See if your state issues this permit, and if so, you should be able to find a PDF of the permit form on a state government website. Once you print this out and obtain the necessary signatures, you will be all set. Hope this helps!
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