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For younger learners

  • Early Years Foundation Stage

Stairs

Age 5 to 11
Challenge Level Yellow star
  • Problem
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Here is a solution to STAIRS, which we very happily received from Hannah of West Flegg Middle School, Norfolk. She writes:

Numbers 1, 5, 8, 11, 12, 13, 14, 15, 16, 17 start with one up then two across. Only number 10 starts with 2 up at the beginning. Number 18 and Number 2 have one up and then 3 across.
1. 2. 3. 4.
5. 6. 7. 8.
9. 10. 11. 12.
13. 14. 15. 16.
17. 18. 19. 20.

Biggest and smallest:-

This is my biggest

This is my smallest

Then:-

14 on the first sheet - No 19.
15 on the sheet - Nos. 14, 2, 3, 6.
16 on the sheet - No. 9.
17 on the sheet - Nos. 8, 13, 18.
18 on the sheet - Nos. 4, 11.
19 on the sheet - Nos. 1, 12, 13, 16.

22 on the sheet - No. 10.
23 on the sheet - No. 17.

And so on... you can just add one to the last square, up the top if you like. I added them up at the top of the last three.

She went on to extend the challenge! WELL DONE

I wonder what would happen if it were 5 along and four up?

The amount would be smaller all the time but the method would be the same.

She also looked at 5 by 6 and 6 by 5. She finishes by saying:

I wonder what would happen if you could have two sets of steps?

e.g.,

Bernard says "Well done, a good approach. I liked the way you had a go, then sorted them into an order, put in the missing ones, and saw how it was just going to go on. Then you asked a further question, and explored it a little. And you finished with a brand new question. Keep up this good work all of you!''


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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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