Applying for college, yes. Applying for loans at 15? No. In the U.S., loans are generally applied for on an annual basis and disbursed on a semester basis. So once again, we return to these people being 18-22 (adults).

My actual point was that yes, parents/teachers/principals/other adult advisers do bear some responsibility, but let's also not pretend the actual students are unable to reason about future income and debt.