As science grows in complexity, science teachers face an increasing challenge of helping students interpret models that represent complex science systems. Little is known about how teachers select and use models when planning lessons. This mixed methods study investigated the pedagogical approaches and visual models used by elementary in-service…

In this paper we focus on variation of the design and the implementation of a specific task during three mathematics lessons in the 8th grade in a learning study (Marton & Tsui, 2004; Runesson, 2008). The theme of the lesson was division, with a denominator between 0 and 1. The teachers wanted their students to understand that when dividing…

By providing sustained, embedded professional development over the course of a school year--as well as involving teachers in creating high-quality assessment tasks, implementing the assessments with students, and tying assessment directly to instruction--the authors increased the value that their teaching community places on mathematical…