I have worked on several DOS conferences over the years. What I like most is that their novel format is a real opportunity to present something in detail and provide lots of relevant examples of how to use the ideas in class. I give lots of talks and usually I have to pack everything into 45 minutes. The DOS conferences allow me to cover much more material and much more in-depth. It is also nice to be working with practicing teachers, who really appreciate and understand the ideas and their application in the class.