The Development of The Concept of Speed and its Relationship to Concepts of Rate * Patrick W. Thompson Department of Mathematical Sciences and Center for Research in Mathematics and Science Education San Diego State University Thompson, P. W. (1994). The development of the concept of speed and its relationship to concepts of rate. In G. Harel & J. Confrey (Eds.), The development of multiplicative reasoning in the learning of mathematics (pp. 181-234). Albany, NY: SUNY Press. Running Head: Concepts of Speed and Rate * I wish to express my deep appreciation to Jim Kaput, Les Steffe, and Guershon Harel for the long conversations we have had on the issues addressed here. Research reported in this paper was supported by National Science Foundation Grants No. MDR 89- 50311 and 90-96275, and by a grant of equipment from Apple Computer, Inc., Office of External Research. Any conclusions or recommendations stated here are those of the author and do not necessarily reflect official positions of NSF or Apple Computer.