Senteo is a remote control that each student uses to answer questions actively on the screen
You can see who has answered, who has yet to answer, how long it takes them to answer and what their answer is to the active question.
This gives instant feedback so that corrections can be made quickly.
Students can see how other students can get the same wrong answer and we can determine why they came up with the answer solving problems before they learn something that is not right.
You can get many premade question sets from Smarttech.