Consider that colorful photographs, eye-catching illustrations, and captivating images intended to make textbooks more appealing may actually distract students from the lesson at hand. Or that asking students to simply solve math problems might not be as effective as having them explain the steps of solutions that are already worked out--even some that are worked out incorrectly. This article presents an examination into the application of cognitive science to the curriculum design of middle school-level mathematics. It describes a proposed revision of a mathematics curriculum with particular attention to visual imagery, conceptual understanding promotion through new exercises and studies of old solved problems, and the use of targeted feedback testing. [This article was first published in WestEd's R&D Alert, Vol. 15, No.1, 2014.]