Student can bring their own credit or debit card as long as it has a chip. There may be fees to take money out of an ATM depending on your bank. We suggest students making one withdrawal upon arrival with enough cash so they won't have to use an ATM again and get a fee every time.
Most banks need to be called ahead to tell them that you are traveling out of the country to Spain for the dates of the trip.
If a student does not have a credit or debit, they can go to any AAA branch and get a pre-paid Visa debit card. You can add money while they are in Spain if you need to.