Gleen D. Berkheimer, Charles W. Anderson
and Theron D. Blakeslee
with the assistance of Okhee Lee,
David Eichinger, and Karen Sands
The Institute for Research on Teaching
College of Education
Michigan State University
This work is sponsored in part by the Institute for Research on Teaching, College of Education, Michigan State University. The Institute for Research on Teaching is funded from a variety of federal and private sources including the United States Department of Education and Michigan State University. This material is based upon work supported by the National Science Foundation under Grant No. MDR-855-0336. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the position, policy, or endorsement of the funding agencies. All rights reserved by Michigan State University.