There is a great deal to say about how to use appropriate tools strategically, which is Mathematical Practice 5 from the Common Core State Standards. It is simple to say that this standard is about using a compass, protractor, ruler, or similar physical tool. There is so much more to using tools than just the use of physical objects. As I read in an article recently, even extremely simple tools are the product of a long period of experimentation, experience, observation, reflection, and recollection. This is the focus on tools I will address in this post.