The Acellus Learning System, a project of the International Academy of Science, was created with the goal of making a science of the learning process. Acellus operates as a comprehensive system which delivers instruction to students by computer, manages assignments, provides student assessments, and maintains student records. More importantly, Acellus provides an array of advanced features enabling it to diagnose deficiencies in student understanding, to provide customized personal instruction when needed, and to constantly analyze the effectiveness of the teaching process. Acellus is now used throughout the US at more than 10,000 schools, both public and private. In the preferred deployment, it is used as part of a blended learning system where instruction is provided over Acellus as well as by qualified teachers at the local school. For more information on acellus, visit www.science.edu/acellus