This week we looked at chance, or probability, since it often subtly influences the world around us and confounds our expectations. First we broke up into pairs, each pair rolling a single die many times to count the number of times each number was rolled. Some very impressive addition was applied by several students to combine everyone’s results:
most numbers received equal counts, although 6 appeared to roll a little too often…
We then tried with two dice, counting the number of times each combined value (that is, 1 to 12) was rolled. When we added up the scores we found some values were much more frequent: 2 and 12 hardly happened at all, while values in between happened many times. 1 was never rolled, but the children immediately realised that could never happen. Several guessed that the reason 2 and 12 were infrequent was because there’s only one combination possible for each (1+1, and 6+6) whereas a number like 6 has many combinations (1+5,5+1,2+4,4+2,3+3).
We finished with a different game by flipping a coin and trying to guess the outcome, leading to an experiment: I hypothesised that wishing made the coin land heads-up, and we tested this by all wishing for heads at the same time and checking the outcome. Heads! But to be more sure we repeated, and after many tosses we finally got tails. So we disproved the hypothesis, but it didn’t rule out that wishing NEVER works. That’s a limitation of scientific theories, and the humility of science: as Einstein once supposedly said “No amount of experimentation can ever prove me right; a single experiment can prove me wrong.”
Science Club facilitator