Environmental law courses are offered as elective courses in the second and third years of JD study at many American law schools. Curricula vary: an introductory course might focus on the "big five" federal statutes—NEPA, Clean Air Act, CWA, CERCLA (Superfund) and Resource Conservation and Recovery Act (or, alternatively, the Federal Insecticide, Fungicide, and Rodenticide Act)—and may be offered in conjunction with a natural resources law course. Smaller seminars may be offered on more focused topics. Some US law schools also offer an LLM or JSD specialization in environmental law. Additionally, several law schools host legal clinics that focus on environmental law, providing students with an opportunity to learn about environmental law in the context of real world disputes involving actual clients.