Quiff, Boot and Genie are locked in a room and have to find the mean number of eyes in the jars. They explain what the mean, median and mode are, and demonstrate how to work out the mean.
Check pupil understanding of mean by asking the question "There are three people waiting to see the head teacher. They have a mean age of 30. Who could they be?" Consider a range of scenarios where ages are very similar (or the same) and ages are very disparate. Children might like to investigate the mean of sets of consecutive numbers. For example the mean of a set of three consecutive numbers is always three times the middle number. What happens with a set of 4 or 5 consecutive numbers? What generalisations can you make?