Sell the books back to the bookstore at the end of each semester. Most bookstores have a buy-back program and it is the easiest method of selling the books. It is also the least profitable for you and the bookstore will turn around and sell the book for much more than they paid you.
Place an ad in a local classifieds system. Depending on where you live this will be the Internet or a physical paper. Arrange to meet with potential buyers and sell the books for about 10 percent less than the bookstore. Use the fact that your books are cheaper than the bookstore's as a selling point.
Place paper ads on the nursing school bulletin boards. List the books that are for sale and provide a contact phone number. Offer a discount for students who buy multiple books in a single purchase.
Target a large audience by listing your books on book broker websites. Amazon.com is a common marketplace for used books but there are also numerous websites that deal specifically with school text books.
Follow up with customers who are in the beginning phases of nursing school. You can sell your books to the same students throughout the course of several semesters if you stay in contact.