In my room, we have "expert badges." Students get to be an "expert" and help others if they're finished and fully understand the activity. It allows for the "ask 3 then me" principle to be used. Just print, laminate, and put on lanyards! I originally had mine on a mix-matched set of lanyards I had collected over the years from different workshops, but Staples sells a pack of 5 and now mine all match!