Larry Sowder


  • 1986–2004: Professor, San Diego State University

  • 1984–1986: Professor, Northern Illinois University
    Summer 1984: Visiting Associate Professor, Oregon State University

  • 1975–1983: Associate Professor, Northern Illinois University

  • 1975–1976: Research Associate, University of Oregon

  • 1969–1975: Assistant Professor, Northern Illinois University

  • 1961–1965: Mathematics and Physics Teacher, and Dept. Chair, North Judson Schools, Indiana

Research interest

My recent interest in college students’ learning of mathematical proof/justification continues, as does an earlier interest in problem solving, especially students’ work on story problem.


The Development of Proof Understanding, Production, and Appreciation. National Science Foundation, 1995–1999. Grant to Purdue University (G. Harel, PI), subcontract to San Diego State University.

Reforming the Preparation and Professional Development of Elementary and Middle School Mathematics Teachers. National Science Foundation, 1994–1998. (J. Sowder, PI)

Linking the Mathematical Operations to their Applications. National Science Foundation Grant MDR 8850566, 1989–1991.


Advanced Mathematical-Thinking at Any Age: Its Nature and Its Development. Mathematical Thinking and Learning, 7(1), 2005, pp. 27-50. (With G. Harel, first author)

Case Studies of Mathematics Majors' Proof Understanding, Canadian Journal of Science, Mathematics and Technology Education. 3(2), April, 2003, pp. 251-167. (First author, with G. Harel)

Educating Teachers of Science, Mathematics, and Technology: New Practices for the New Millennium. (2001). Member of National Research Council Committee contributing to the document.

Sowder, J., Armstrong, B., Lamon, S., Simon, M., Sowder, L., & Thompson, A. (1998). Educating teachers to teach multiplicative structures in the middle grades. Journal of Mathematics Teacher Education, 1, 127–155.

Harel, G., & Sowder, L. (1998). Students’ proof schemes: Results from exploratory studies. In A. H. Schoenfeld, J. Kaput, & E. Dubinsky (Eds.), Research in collegiate mathematics education. III (pp. 234-283). Providence, RI: American Mathematical Society.

Sowder, L., & Harel, G. (1998). Types of students’ justifications. Mathematics Teacher, 91, 670–675.

Sowder, L. (1996). Classifying processes of proving. In L. Puig & A. Gutiérrez (Eds.), Proceedings of the 20th conference of the international group for the psychology of mathematics education (Vol. 3, pp. 59–65). Valencia, Spain: University of Valencia.

Sowder, L. (1995). Addressing the story-problem problem. In J. T. Sowder & B. P. Schapelle (Eds.), Providing a foundation for teaching mathematics in the middle grades (pp. 121-142). Albany: SUNY Press.

Shigematsu, K., & Sowder, L. (1994). Drawings for story problems: Practices in Japan and the United States. Arithmetic Teacher, 41, 544–547.

Sowder, J. T., Bezuk, N., & Sowder, L. K. (1993). Using principles from cognitive psychology to guide rational number instruction for prospective teachers. In T. Carpenter, E. Fennema, & T. Romberg, Rational numbers: An integration of research (pp. 239–259). Hillsdale, NJ: Erlbaum.

Bezuk, N. S., Armstrong, B. E., Ellis, A. L., Holmes, F. A., & Sowder, L. K. (1993). Educators and parents working together to help all students live up to their dreams with mathematics. In G. Cuevas & M. Driscoll (Eds.), Reaching all students with mathematics (pp. 23–44). Reston, VA: National Council of Teachers of Mathematics.

Sowder, L. (1993). A project to link the arithmetic operations and their uses. In I. Hirabayashi, N. Nohda, K. Shigematsu, & F. -L. Lin (Eds.), Proceedings of the seventeenth international conference for the psychology of mathematics education (Vol. 3, p. 249). Tsukuba, Japan: Program Committee of the 17th PME Conference.

Selected Presentations

Reconceptualizing Mathematics: Courseware for Elementary and Middle Grade Teachers. Presentation at the annual meeting of the National Council of Teachers of Mathematics. Washington, DC, April, 1998. (With J. Sowder, J. Bernhard, L. Clement).

Classifying Processes of Proving. Annual Meeting of the International Group for Psychology in Mathematics Education, Valencia, Spain, July, 1996. (With G. Harel, who presented the paper.)

Interviewing Undergraduate Majors about Proof. Joint Meeting of the American Mathematical Society and the Mathematical Association of America, Orlando, January, 1996. (With G. Harel; I presented the paper.)

Is "Mathematics as Reasoning" (Standard 3) a Part of the Curriculum? Southern Section of the California Mathematics Council Annual Meeting, Palm Springs, November, 1995.

Revisiting Research on Concept Learning. Seventh International Congress on Mathematical Education, Quebec, 17-23 August 1992. (Geometry Working Group)

(1) What's Important about Multiplication and Division: Their Meanings. (2) The Various Meanings of the Four Basic Operations: How You Can Teach for Understanding. Presentation and workshop, National Council of Teachers of Mathematics, Eugene, OR, 19-21 March 1992.

Larry Sowder  

Larry Sowder
Professor Emeritus of Mathematics


E-Mail: [email protected]