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Simplifying Doughnut

Age 14 to 18
Challenge Level Yellow starYellow starYellow star
  • Problem
  • Student Solutions
  • Teachers' Resources

Why do this problem?

This team-building task is designed to develop learners' team-working skills. If you wish to learn more about these skills and find other team-builder tasks look at this article.
This task depends upon members of the group noticing the needs of others and responding. It requires learners to:
  • respond to the needs of others
  • consider the needs of the whole group
  • help others to do things for themselves.

Possible approach

Share the purposes of the activity and the rules with the group.
Ask team leaders to hand the cards out randomly- four dominoes to each group member.
If you have more than four people in a group then use an observer to ensure the team obeys the rules and notes when there is evidence of members of the team responding to the needs of others, as well as to place a hint card in the middle if one is needed.
  • Here are the rule cards.
  • You can find the Hint cards here.
As teams finish, ask them to discuss the key things they have learnt about working together. Use observers to feed into the discussions. Then spend some time discussing observations you have made or teams have made as a whole class activity, talking about how they might work more effectively next time.

Key questions

As this task is designed to be carried out in silence, the use of key questions is inappropriate during the task but can inform discussion of team behaviours when the task is complete.
  • Can you give any good examples of when someone noticed what you needed and tried to help?

Possible extension

The dominoes can also be arranged into a pair of doughnuts or one large doughnut. Ask the team to try and create these shapes.

Other skill-building tasks can be found by going to this article.

Possible support

Other skill-building tasks can be found by going to this article.









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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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