​About the Author Lawrence Leff is former Assistant Principal, Mathematics Supervision, at Franklin D. Roosevelt High School, a large urban high school in Brooklyn, New York. Mr. Leff served on many local mathematics committees including a term as a member of the New York State Regents Exam Preparation Committee. He has a strong interest in developing and publishing reader friendly mathematics review courses. Mr. Leff has used his many years of experience teaching and supervising all levels of high school mathematics classes, including SAT Math preparation classes, to create a highly effective SAT math study program. About the Publisher Many great things begin with a tiny spark, and for Manuel H. Barron that spark came from a mimeograph machine in the basement of his Brooklyn, NY, bookstore in the late 1930s. People from the community asked Mr. Barron for books to help their children study for the New York State Regents exams. After realizing there wasn't anything available, Mr. Barron created his own study guides. Now, more than 80 years later, Barron’s continues to help millions of learners worldwide prepare for their next steps. With offerings from pre-college prep to world language guides and professional certification exams, Barron’s wants to be part of your success story no matter what learning path you’re on. You can trust Barron’s to provide exceptional products created only by top experts with years of experience in education. From generation to generation, our mission remains the same: Learn, grow, and succeed with Barron’s throughout your life-long learning journey.