I work in a financial services office and it's that time of year when many people are accessing their 529 plans to pay for college costs. I have gotten a lot of questions about whether these funds can be used to pay for computers, school supplies and transportation. The computer is the only item that "may" qualify for 529 funds, and that's currently only if SPECIFICALLY required for a class.
People are really frustrated to find out that either (a) their student has a full ride but all the money they saved for college is in the 529 and they can't use it for these items or (b) they are already using the 529 money to pay tuition and other qualified expenses, and do not have other money set aside for additional expenses.
So, my tip for you (and myself as I have a HS senior) is to make sure you have some money earmarked for college expenses that is NOT in a 529 plan or Coverdell ESA. I was contributing to my son's 529 but stopped and will keep some back in money market to cover this type of expense. Just because an expense appears on the COA does not mean it qualifies for these tax sheltered funds.