Assessing student learning traditionally involves determining whether students can solve a certain percentage of problems correctly, under the assumption that this achievement indicates they have the knowledge and understanding they need to progress to new topics. This article explores what teachers can learn from looking closely at student…

Data (Schoen et al. 2016) suggests that because many students' understanding of subtraction is limited by thinking about the operation only as take-away or by using a default procedure, such as the standard subtraction algorithm in the United States, second graders are much more likely to solve 100 minus 3 correctly than 201 minus 199. This…

Teachers face many challenges helping students meet the expectations set forth in the Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010). CCSSM content standards not only introduce new concepts at each grade level but also require teachers to learn new terminology for old concepts and consider how students' understanding of concepts…