There are certain classic physics labs. The ruler-reaction time lab is one of those. It is simple, requires little equipment, but gives students something they can relate to.
Good Artists (Teachers) Borrow, Great Artists (Teachers) Steal
I can use a cell phone in class?While I had my guys, working in teams of three with one being tested and one dropping the ruler and one receiving the text message from the testee, using cell phones, I realize now that any active distraction will do. I could even have them using calculators. What matters is that the brain is trying to actively focus on two things at once. I could have the third team member ask the testee to use a calculator to calculate something "What is 5+7-5*25.......no I meant 23+3.....".
The results were as expected; the average distracted reaction time is more than the undistracted reaction time. And most students will see their distracted times more deviated than the undistracted times. The lesson here is that while you might get away once or twice with texting while driving, you cannot always count on a good reaction time.