Redundancy effect has been investigated in many controlled experimental studies, however, it is seldom investigated whether the same redundant material may cause different results in classroom, which is a major learning place for students. Considering that it is not easy to control the internal validity in classroom environment, this study…

International comparisons have highlighted that the U.S. mathematics curriculum, both in terms of curriculum influences (e.g., textbooks, standards) and actual instruction, is broad and shallow. Standards-based reform is explicitly designed to improve coherence and reduce redundancy across grades. This article evaluates the redundancy of…