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How do kids understand negative numbers?

Professors Lamb, Bishop, & Philipp Research Mathematical Thinking


Have you ever wondered why 6 – -2 = 6 + +2? Is there any such number as negative zero? What percentage of second graders do you think could solve 3 – 5 = ?, and how might they solve that problem?

Drs. Lisa Lamb, Jessica Bishop, and Randy Philipp asked themselves these and other questions and have found surprising answers from their research on children’s mathematical thinking in K–12 classrooms. The three mathematics educators were awarded a $1.6 million grant from the National Science Foundation to study students’ ways of reasoning about negative numbers in Grades 2, 4, 7, and 11. On the basis of their findings, they have conducted professional development on the teaching of integers, written and presented broadly for teachers and researchers, and, at the invitation of the authors, revised the integers section in textbooks for mathematics content courses for prospective teachers.  Additionally, several of SDSU’s graduates from the MA program in K-8 Mathematics Education and students from the Mathematics and Science Education Doctoral (MSED) program engage in research and professional development and present with the project team.