AMSCO is dedicated to providing high quality, inexpensive textbooks and support materials to the educational community. Our course texts, review, and test prep books reflect national and state standards for curriculum and assessment. We provide a growing list of State Proficiency Preparation titles custom tailored to meet the specific requirements of each of several states. In addition to answer keys, many of our titles are accompanied by Teachers' Manuals, which provide lesson plans and suggestions for instruction.