Is it free to use images of ocean animals found online for educational purposes?

In general, most images can be displayed and discussed for free in any classroom as part of the doctrine of fair use in the Copyright Act of 1976. However, the doctrine of fair use may not apply to printed materials, classroom projects or education blogs.

The doctrine of fair use generally states that material used in the classroom for teaching, research and scholarship does not infringe on copyright law. To avoid any risk of copyright infringement, though, it may be safer to go through a site such as CreativeCommons.org that provides content that is free to reuse with proper accreditation.