Former Officer in the United States Navy and the Naval Reserve
Co-author, Algebraic Thinking: Models for Problem Solving, (Dubuque, IA: Kendall/Hunt Publishing, 2007
Professor Shaffer earned his M.A. in Mathematics from Youngstown State University and his B.S. in Chemical Engineering from Pennsylvania State University. He earned his NCATE Accredited Certification in Secondary Education Mathematics from Pennsylvania State University. Professor Shaffer has a long history in mathematics education and served as a Lieutenant Commander Unit Training Officer in the United States Navy.