Why do this problem?
This activity , when done practically, usually gives great
excitement and leads to an extensive discussion as learners try to
explain their reasoning to one another.
Possible approach
You'll probably get the
best discussion and thoughts from the pupils if you 'act' out the
situation. You are the ice cream vendor with a selection of cards,
counters, cubes etc. to represent the ice cream. Make sure that the
class can see the choices that the previous pupil(s) made and
encourage them to check if they've kept to the rule, helping as
little as possible.
Once they have got the
idea, invite them to work on the problem, perhaps in pairs. Allow
them to make their own decisions as to the equipment they use and
the way they record - sharing these can be just as valuable as
sharing solutions.
This activity would lend
itself to a display and so you may want children to work on large
sheets of paper which could be the stimulus for a plenary and could
then be put straight up on the classroom walls. You could invite
some children to explain how they have found different ways of
seven children having ice cream. Draw attention to those who have
found a systematic way of finding solutions.
Key questions
Why did you choose that
flavour?
Is there a way of
choosing to let more pupils have a choice?
Possible extension
As the problem suggests,
the thinking can be extended by looking at larger numbers of
flavours.
For the
highest-attaining
From the "Possible
Extension" the challenge would be to find a general formulae that
would take into account the number of flavours and how many scoops
were alloed each time to produce the largest numbers of hungry ice
cream addicts who could have their fill. Then there would be the
need to prrove it to be correct.
Possible support
This problem is a good
context in which to try to stand back and encourage pupils to
support each other and explain ideas themselves. Working in pairs
might be an appropriate way to support this.