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'Guess the Function' printed from https://nrich.maths.org/

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Why do this problem?

This task encourages learners to ensure all members of the team participate, share their reasoning, listen to each other's opinions and reflect on the outcome. This is one of a series of problems designed to develop learners' team working skills. Other tasks in the series can be found by going to this article.

Possible approach

The task is designed to work with teams of four, taking it in turns to be the "Ruler."

Using a fifth person as an observer means that feedback can be very specific and works well either using another learner or an adult.

The aim is for the team to discuss and agree before selecting any card to be tested by the Ruler. Does the function obey the rule on the chosen rule card?

Here are the function cards.
Here are the rule cards.
Guideline cards for the team and Ruler can be used to focus the learners' attentions on the main aims of the task.

One of the roles of the Observer is to check discussion takes place before a decision is made and that the Ruler only responds if they feel everyone has contributed to the decision. Guideline cards for the Observer can be found here.

When teams have finished working on the task it is important that they spend time discussing in groups, and then as a whole class, how well they worked as a team. They can consider what they have learned from the experience and what they would do differently next time, particularly in terms of how to listen to each other and ensure that all members of the team participate. Your own observations, as well as those of observers, might inform the discussions.

Key questions

  • Was there a choice of house to test that was particularly useful? Why?
  • Were there any ideas that proved really helpful?
  • How well did you listen to others in your group?
  • How did you ensure that everyone had a chance to contribute?

Possible extension

Learners may like to try one of the other 'Guess the rule' tasks, which can be found by going to this article.

Possible support

You may wish to give a copy of all, or a selection, of the rule cards and function cards to the team so they have a list of possible rules. There are a set of cards with just quadratic functions in this task. Other team-building tasks can be found by going to this article.