Recommended Books:

Critical Encounters in High School English: Teaching Literary Theory to Adolescents by Deborah Appleman
Critical Theory Today: A User-Friendly Guide by Lois Tyson

Websites: - This site has definitions and essays on various critical approaches including feminist criticism, the new historicism, psychoanalytic criticism, reader-response criticism, structuralism, marxist criticism, the new criticism, formalism, and post-colonial criticism. - This site lists various critical/theoretical approaches with definitions, key terms, and suggested websites and books.