I agree with @pk . There are no special tax requirements, but for your own protection, you should have a written agreement with the parents as to what the money is to be used for and what it is not; you should have a separate bank account; and you should keep good records.
One final thing I will add, is that you should not intentionally try to keep your transactions under $10,000 to avoid US banking reporting laws. If the parents want to transfer (for example) $20,000, just do that, don't make it 4 separate transfers of $5000 each. In some cases, it can be a legal problem to "structure" your transactions to avoid the reporting rules, even if the purpose of the transfers is entirely innocent and legal.
