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  • Early Years Foundation Stage

Alien Counting

Age 7 to 11
Challenge Level Yellow starYellow star
  • Problem
  • Getting Started
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There is a lot to explore in this challenge!
Have you tried writing out numbers above 7 for each alien?
Can you find numbers that the aliens used to count the children in the classroom that look the same to the humans looking at the masks?
Do let us know what you discover.Please don't worry that your solution is not "complete" - we'd like to hear about anything you have tried.
Teachers - you might like to send a summary of your children's work.

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Page Numbers

Exactly 195 digits have been used to number the pages in a book. How many pages does the book have?

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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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