Copyright is a legal regulation that prevents others from certain uses of a creator's material. Sometimes, educational institutions can get past those regulations due to exemptions and there is always Fair Use. But using these options can be vague and confusing. As stated by the Copyright Office in Circular 16A, "One way to make sure your intended use of a copyrighted work is lawful is to obtain permission or a license from the copyright owner".
Getting permission doesn't always require paying. Often if the material is from someone affiliated with an educational institution, they are more than happy to provide you with permission. Your part is to determine if they still have the right to do so. Below are some steps that show you how to procede with getting permission.