Absolutely yes. You have to pay taxes on any and all income from all sources not used for "qualified" education expenses. For scholarships/grants the only qualified tax-deductible education expenses are tuition, books, and lab fees. That's it with no exceptions. All excess scholarship monies, regardless of what it was used for, is taxable income to the student.
For 529 funds reported to you on 1099-Q, the only qualified education expenses for those funds are tuition, books, lab fees *and* room and board. That's it with no exceptions. Any excess is taxable income to the student.
So if you've been using scholarships/grants for *everything* there is no doubt that you have some taxable and reportable income. Of course, any earnings on your investments is also reportable and taxable. But I think you know that goes without saying.
