I am in tech heaven this week. I have started using a new student response system in my room by SMART. I upgraded from the Classroom Performance System that I had for 5 years and couldn't be happier with the switch. SMART actually gave us a HUGE discount for trading in the old system toward a new one. Check it out.....it's called the SMART Student Response PE. They also have a primary and special needs "clicker" called the LE. See the picture below the PE. This works with the SMART Notebook software (which is included if you don't already have it).
Check it out!!!! The kids are engaged and loving it! Plus......you can import tests that are already made (PDF) AND AND AND it will do item analysis for you (exported to Excel).