How many leaves are on a tree? You may have wondered about the answer to this question, but who has the patience to sit and count?
Gather your students in groups around a tree (which they can reach) in the autumn and ask each group to estimate how many leaves are on the tree. Give them a time limit, as some students will insist on counting them.
Talk about how estimates are the closest guess, based on observation, and how mathematicians refine their estimates through using more accurate means of estimations. To demonstrate this, have each group find a branch of the tree that they think has the average number of leaves. Then, have students count the leaves on that branch and compare their answers.
Help them estimate the total number of leaves on the tree by multiplying the number of leaves on that single branch by the number of branches on the tree. Compare their answers to their original estimate, and have them discuss which one is probably a more accurate estimate.