PrepTest 83 is the actual LSAT that was administered in December 2017 and includes an answer key and writing sample prompt. Practicing with previously administered LSATs is one of the best ways to prepare for the test. The Official LSAT PrepTests are published by the Law School Admission Council (LSAC), the organization that produces and administers the LSAT. For practice on actual, previously administered LSATs at an unbelievable price, you can't beat the Official LSAT PrepTests.