Your child may have come home telling you they participated in a clicker activity.  What in the world is that?????  What they are referring to is an electronic student response system.  I wrote a grant a few years back to purchase this system.  Each student gets a small credit card sized unit to use to answer questions I present in a power point presentation.  The students select an answer by pushing a button on the unit which sends a signal to a receiver on my computer.  Once everyone answers, I stop the polling and a graph of all answers is displayed on the board.  We then discuss the answer and can immediately address any misconception the students may have.  This is a great learning tool and the students seem to love it.  I use this system a couple of times a month.  This was an expensive system to purchase, and I want the students to be very careful with the handling of the individual units.