Remember the lovelorn cartoon character plucking petals from a daisy saying , “She loves me, she loves me not?”. Most students do. I ask them, ‘Using this method is he more likely to discover that she loves him or doesn’t?!’ We vote on it.
We discuss how we can test this question. I give them hints like ‘if there’s an odd number of petals how will it end up?’. So then the discussion becomes ‘do daisies have an odd or even number of petals?’ If the daisy has an odd number of petals she will ‘love him’; if even she won’t. We vote on it, and the class hypothesis is the one, odd or evens, which has the most votes.
We test it by collecting lawn daisies and counting their petals. Count at least 100 daisies. Record the numbers, divide into odds and evens, and make a bar chart. Amazingly it is always almost exactly a 50:50 split!
I have used this practical with a wide range of ages (9 to 15) and abilities. More able groups could count more daisies and make bar charts of the numbers. The range I have found is 20’s into the 70’s!
@JaneStill2 Dorchester, Dorset – Science supply teacher