Nuclear chain reactions

This works best in an open area such as the hall or gym.

Students are placed in rows all facing one way. The first row has two students, the second four, the third eight, and the fourth sixteen.

Each student has two ping pong balls and is told to aim for the two students in front of them. BUT they cannot throw until they are hit by a ping pong ball.

I start the chain reaction off by throwing a ping pong ball at the first two students. They then throw theirs at the row in front, etc etc. After a couple of goes they get the idea. Then we improve the learning by:

a making students shout Bang! as they throw (energy release)

b pairing students and making the pair step apart when they shout Bang! (fission)

c introducing catchers in between the rows as control rods

d move the rows apart so there are fewer hits per row (use of a moderator)

If there is a pupil who I suspect may act improperly, I get them to act as an observer in order to report back to the class what they have seen.

What made this activity go well

• Out-of-class activity is always motivating.
• It is silly but it gets lots of points across.
• Students remember it and why they did it.

Last updated: 20 May 2008