Establish a study group.
Total the amount of money needed for textbooks for one student. Divide the total by the number of people in your study group.
Have everyone in the study group pitch in the same amount of money. Purchase one copy of each required book.
Distribute the book in a way so that everyone in the study group will have a copy of the textbook. You could buy the electronic version of textbooks and email copies of it to your classmates. You could also take digital photographs of physical textbooks; make copies of the files and electronically transfer the scans or photographs to classmates.
Find former students of the class who are willing to rent textbooks. Renting is an option you can pursue if you cannot raise enough money for the total cost of the textbooks.
Use your school or local library to save even more money. However, be sure to reserve your textbooks before the semester starts.
Take turns having custody of physical textbooks throughout the semester. Keep in contact with all your study group buddies during important exams or when major papers are due.
Sell all your textbooks when the semester is done. Divide the profits between the study group members.