At the MTNA Conference I had the privilege of meeting Bonnie Slaughter, the creator of this ingenious approach to theory. I like to think of it as the text messaging approach to music theory. 🙂
Theory Strips are a 10-level program that organize music theory concepts into strips that can easily be completed one day at a time. I love this approach, especially for students who might be overwhelmed at the prospect of working through several pages at a time.