Promethean Planet offers an online course for Learner Response Systems – ActivExpression, ActiVote, ActivSlate, & ActivEngage. There are very well done tutorials that break down each step of the process. I looked at the sections on ActivExpression (which I recently got in my classroom) and the ActivEngage (which is on the net books in a room I travel to). Much of the information was prior knowledge, but I learned a lot about evaluating and viewing the results.
After you are confident about the material there is an assessment. If you score 100% on the assessment, there is a certificate of completion.
I would highly recommend the course for anyone who uses any of the Activ student response systems. I was quick and informative. I was able to skip parts I knew and go straight to the areas that I was unsure about.