Use it as a valuable lesson
Found money is a very unexpected but pleasant surprise. It also gives you a chance to understand how finances work and how you can make them work in your favor, learn how important and liberating it is to be debt-free and discover other useful financial information for you to use in the future. If you are a good student, everything you learn can not only be used to increase your bank account but also your knowledge bank.
Something else you could learn is How to Make the Most of Your Tax Refund.
