The codevelopment of children’s fraction arithmetic skill and fraction magnitude understanding.

The importance of fraction knowledge to later mathematics achievement, along with U.S. students’ poor knowledge of fraction concepts and procedures, has prompted research on the development of fraction learning. In the present study, participants’ (N = 536) development of fraction magnitude understanding and fraction arithmetic skills was assessed over 4 time points between 4th and 6th grades. Latent state-trait modeling was used to examine...