Surveys were used to examine mathematics teachers (15) on their ability to solve similarity problems and on their likely implementation of lesson objectives for teaching similarity. All correctly solved a similarity problem requiring a traditional static perspective, but 7 out of 15 failed to correctly solve a problem that required a more transformational perspective. A set of 10 lesson objectives on similarity were composed using Geometry textbooks, using the Common Core State Standards (CCSS), (NGA Center and CCSSO 2011), and using some generated by the authors. When asked to select from the list of objectives the ones they would most likely implement, teachers favored traditional textbook objectives that might be presented using a static perspective, rather than similarity transformations, manipulatives, or technology that might support a more transformational perspective. In fact, these were among the objectives most likely not included in their lesson plans. |