some of the finer points of using them:

Ready, Set, React: Getting the most out of peer instruction using clickers

I liked how this source had me consider when and how to start a clicker poll, how to consider the answers I got and the variations I could expect to see.

These were also helpful:

The Clicker Resource Guide: (http://www.cwsei.ubc.ca/resources/files/Clicker_guide_CWSEI_CU-SEI.pdf)
CWSEI has some great resources on its Clicker page.

I still think I need better questions though. Most of mine are very simple, “are you paying attention?” and I’d like more challenge questions that expand on student understanding.