Dad Blogs: Fun and Surprising Statistics for Kids

There is an interesting little puzzle called the Monty Hall problem that is a great way to introduce statistics for kids. There are different ways to present the problem (one requires goats), but for our kids, we used three cups and M&Ms. The kids (and Lily’s doll) took turns hiding one M&M under one of the three cups. We asked Mama to pick one of the cups. Before lifting the cup, we pick up one of the other cups and reveal that it does not have an M&M underneath. Is it to Mama’s advantage to switch her original choice?

MaryAnne’s intuition (as well as most people’s intuition) is that it doesn’t matter—that there is just a 50% chance of being right or wrong—so we decided to play a game to test her hypothesis. If MaryAnne’s original guess is right, she gets to keep the M&M; otherwise the kids get to keep whatever is under the other cup. To keep track of our data, we collected the M&Ms on a piece of paper with an area for “Mama” and an area for “Kids”. The kids loved getting high-fives and adding the M&Ms to their pile as the experiment progressed, but it was a little difficult to keep the kids from eating our data.

Much to Mama’s disbelief (and to the kids’ great excitement) the kids got a little over twice as many M&Ms!

I didn’t go over the mathematical proof that you are expected to do twice as well if you switch, but it did get the kids excited about counting!

By the way, interested readers can play a version of the game with goats here.