In this workshop, participants will help middle school teachers learn approaches to teaching functions using visual models. Participants in this workshop will become familiar with strategies to help students develop a strong conceptual understand of functions and with tasks that allow students to explore situations of both linear and non-linear functions. Participants will also engage in creating classroom tasks to help students make connections between multiple representations of functions. Participants will evaluate a variety of applets throughout this course, and they will conduct an interview with a small group of students about their experiences using an applet. In the final project for this course, participants will design a lesson plan using an applet to explore the concept of function.