Why do this
problem?
This problem offers a context in which to think about relative
size and gives children chances to estimate quantities.
Possible approach
It might be appropriate to read the book "The Man" (by Raymond
Briggs) with the class prior to working on this task.
Before looking at the problem specifically, it would be worth
investigating how much liquid different everyday items hold, for
example spoons, bowls, bottles and jugs. This practical exploration
could be done in a water tray or simply a large bucket or bowl with
small groups of learners.
Once the class comes onto looking at the questions, it is
important that you encourage them to make estimations and explain
how they arrived at their answer. It may be appropriate for you to
share your own methods of estimating, particularly when it comes to
the capacity of the man's mug. It would also be helpful to have a
mug, ruler and measuring cylinder to hand so that everyone can
check whether their estimates are realistic.
Key questions
How long is one centimetre? Ten centimetres? So how high do
you think a mug might be?
How did you come up with your answer?
Can you think of anything that you know holds about a litre of
liquid?
How much do you think a mug might hold?
Possible extension
You could challenge children to articulate the relationship
between the relative size of the man and one of them. Is the man
about twice as small as us? Five times smaller? Ten times smaller?
Will this relationship hold for everything?
Possible support
Some learners might find it helpful to have a series of tasks
which requires them to estimate and then measure concrete items in
the classroom before going on to estimate measurements of items
they are visualising.