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Let's Divide Up!

Show us how you could answer the questions using
- words?
- pictures?
- numbers?
- objects?
- other ways?

 

 

It's Jola's birthday and she is having a party. She has $24$ cup cakes to share equally between $3$ plates for the party.How many cakes will go on each plate?

 

 

 

 

 

 

There are $8$ children coming to the party. They are all going to the cinema. How many cars will they need to take them there? Each car will hold $4$ children and they will each need a driver too.

 

 

 

 

Jola is going to give everyone some chocolate eggs to take home at the end of the party. They fit into egg boxes which hold $6$ eggs each. Will $50$ eggs be enough for each of the $8$ visitors to have a box to take home?

 

Why do this problem?

At first glance this looks like any collection of word problems about division. However each different scenario draws attention to a different way of thinking about the idea of division:
  • sharing, grouping
  • successive subtraction
  • or the inverse of multiplication.

An article which explores different ways of thinking about division can be found here.

Whilst the children are working on each question, the teacher can observe just how they are considering it, and this may be somewhat different from the taught approach. Given the opportunity, children often have their own ways of working.

 

Possible approach

In each case it would be possible to use a range of representations of the situation to help solve the problem and children should be encouraged to explain how they have tackled the problem and arrived at their solution using different resources to help them. Look and listen carefully to hear how they make sense of the question and develop a strategy for solving it.

Talk to the children about how different people do things in different ways and explain that this actvity is all about that -  it's important that the children don't presume that there is one way and one way only to see the calculation.

Working within a pair or small group and tackling one problem at a time can help children to focus more deeply on one task rather than racing through them. You could suggest that they think and talk about what they are going to do before they actually begin.

They may decide to enact with objects or make a picture and just record the answer. Or use these as a prompt to transfer the problem to a calculation which they would record horizontally. Whichever, your observations will allow you to reflect on the children's confidence, language and understanding and possibly what misconceptions they hold.

 

Key questions

Tell me how you are working this out.
What do you think of _____'s way of doing this?
How did you know what to do first?
Is the way you've done this one different from the way you have done the others?

 

Possible extension

Ask the pupils to create stories that involve calculations for their partners to do.
Give the pupils a written form of a division question eg $18/? = 3$ and challenge them to create a story around  it.

Ask the children to create their own division problems based on stories about sharing, grouping, 'undoing' multiplication or successive subtraction. Additional links to other division problems can be found in this article.

 

Possible support

Some pupils will benefit from working with some small toys/dolls so that they can enact the situation before being able to think about the calculation, for example the children could use Lego figures to show the children at the party and counters for the cakes with circles of paper as plates. The physical act of moving objects in different ways while enacting the story can often help less confident children to work out how to think about the division in an appropriate way that makes sense to them.