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For younger learners

  • Early Years Foundation Stage

Take Ten Sticks

Age 11 to 16
Challenge Level Yellow star
  • Problem
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This problem is good to encourage systematic thinking - working from a simple start: two sticks, three, four . . .

Encourage questions like "what could come before . . . . . and what before that" ?

Working backwards from the goal is a mathematical thinking skill.

Especially encourage explanation - accounting for pattern.

There is lots of interest in this simple mechanical process - look out for the triangle numbers!

Above all, if possible, let each insight prompt fresh questions to consider, each new question will illuminate more of the structure.


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Summing Consecutive Numbers

15 = 7 + 8 and 10 = 1 + 2 + 3 + 4. Can you say which numbers can be expressed as the sum of two or more consecutive integers?

Forgotten Number

I have forgotten the number of the combination of the lock on my briefcase. I did have a method for remembering it...

Series Sums

Let S1 = 1 , S2 = 2 + 3, S3 = 4 + 5 + 6 ,........ Calculate S17.

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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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