Affiliations: LRDC, University of Pittsburgh, Pittsburgh, PA, USA.
E-mails: {VanLehn,collinl,lht3,andersw}@pitt.edu | Computer Science Department, US Naval Academy,
Annapolis, MD, USA. E-mail: schulze@artic.nadn.navy.mil | Department of Physics and Astronomy, Rutgers
University, Piscataway, NJ, USA. E-mail: Shapiro@physics.rutgers.edu | Physics Department, US Naval Academy, Annapolis, MD,
USA. E-mails: {treacy,mwinter}@usna.edu
Abstract: The Andes system demonstrates that student learning can be
significantly increased by upgrading only their homework problem-solving
support. Although Andes is called an intelligent tutoring system, it actually
replaces only the students' pencil and paper as they do problem-solving
homework. Students do the same problems as before, study the same textbook, and
attend the same lectures, labs and recitations. Five years of experimentation
at the United States Naval Academy indicates that Andes significantly improves
student learning. Andes' key feature appears to be the grain-size of
interaction. Whereas most tutoring systems have students enter only the answer
to a problem, Andes has students enter a whole derivation, which may consist of
many steps, such as drawing vectors, drawing coordinate systems, defining
variables and writing equations. Andes gives feedback after each step. When the
student asks for help in the middle of problem-solving, Andes gives hints on
what's wrong with an incorrect step or on what kind of step to do next. Thus,
the grain size of Andes' interaction is a single step in solving the problem,
whereas the grain size of a typical tutoring system's interaction is the answer
to the problem. This report is a comprehensive description of Andes. It
describes Andes' pedagogical principles and features, the system design and
implementation, the evaluations of pedagogical effectiveness, and our plans for
dissemination.
Keywords: Intelligent tutoring systems, physics problem solving, web-based homework, physics education research