DES MOINES — Students would not have to pay Iowa sales tax on college and university textbooks under a bill that won unanimous committee approval Tuesday.The House Ways and Means Committee approved House Study Bill 683 23-0 to send it to the full House.It would exempt textbooks sold at all Iowa public and private colleges and universities, including the three universities operated by the Board of Regents.However, the bill makes clear that sales tax must be charged on other materials sold by the bookstores — everything from text books and supplies to sweatshirts, face tattoos, dog bowls and stuffed animals, explained Rep.