This study investigated how elementary teachers in a mathematics lesson study made sense of student learning, teaching, and content, as related to using representations in teaching multidigit subtraction, and how changes occurred over time in their talk and practice. The lesson-study process paved a group talk path along which teacher talk shifted…

Imagine--you must bring water to a hurricane-ravaged area. There is only one bridge and only one truck, and the bridge can only hold so much weight. Your calculations determine if the truck--and its load of water--can make it safely over the bridge. This is a typical challenge during two-week summer camps for third-through fourth-grade students…