Your child's only income was from the summer job, he has no filing requirement. However, if there was income tax withholding from his wages, he should file to get the withholding refunded.
If your child is your dependent, you may qualify for the child credit that could be as much as $3000 if you did not already receive part of it last year. If you are limited by your income from receiving this credit, you may still qualify for other credits for this child/dependent.
