Two studies indicate that Oksapmin children progress from premediational to mediational phases in their use of body parts to compare and reproduce number and that this change generally occurs prior to the development of concepts of number conservation. A third study shows that this general change is manifested in culturally specific ways.…

This brief report from the Indigenous Mathematics Project focuses on the way in which numerical reasoning is changing in the Oksapmin community of Papua New Guinea as a function of participation in new social institutions: economic exchange with currency and enrollment in school. Each of these new institutions means that arithmetic problems are…