For example:
(Note: Taken verbatim from the sticker designed by the Cobb County School District in Georgia.) This textbook contains material on evolution. Evolution is a theory, not a fact, regarding the origin of living things. This material should be approached with an open mind, studied carefully, and critically considered.
…and…
This book was anonymously donated to your school library to discreetly promote religious alternatives to the theory of evolution. When you are finished with it, please refile the book in the fiction section.