Instructor David Hostage has been teaching science at the secondary level since 1976. Since coming to Taft School in 1984, he has taught all levels of chemistry and other sciences as required. He has been Head of the Science Department for two different terms. An active participant in the AP Chemistry community, he has taught the AP course since 1986 and has led workshops in the subject for teachers since 1988. He has been a Reader, Table Leader, and Question Leader at the grading of the AP exam since the early 1990s. For four years he was a member of the Test Development Committee for the subject. Mr. Hostage is the author of a lab manual (Laboratory Investigations: AP Chemistry, Peoples Education) and a test review book (Multiple-choice & Constructed-response Questions in Preparation for the AP Chemistry Examination, D&S Marketing Systems) for AP Chemistry. For many years he was director of the Taft Educational Center, a large professional development institute for teachers from around the world.