LessonSketch is a site for practice-based professional development of secondary mathematics teachers as well as a forum for ongoing conversations about mathematics instruction. It supports the creation, examination, and discussion of scenarios that depict the practice of mathematics instruction.
LessonSketch is built on the idea that representations of mathematics instruction—that is, depictions of interactions between a teacher, their students, and the content—can anchor discussions about the teaching, learning, and mathematics, and provide grounds for practice-based teacher development. The core collection in LessonSketch is a suite of animated sketches of geometry and algebra instruction. As a rule, these animations don't show exemplary instruction but rather they depict conceivable instruction that is expected to provoke individual reflection and professional discussion by LessonSketch members. These reflections and discussions may help professionals create and warrant good instruction.