Happy Numbers

12

23

32

48

50

69

73

81

90

Start Again

Drag the happy numbers from the blackboard into the smiley bin. Drag the other numbers into the unhappy bin. Click the apple for information on how to identify happy numbers.

Instructions

Some numbers are happy and others are not!

To find out whether a number is happy square each of its digits, add the answers and repeat. If you end up with 1 the number is happy!

Sun

E.g. Consider 19

12 + 92 = 82
82 + 22 = 68
62 + 82 = 100
12 + 02 + 02 = 1 which means that 19 is a happy number.

Your mission is to sort the happy numbers from the others!

 

Drag the happy numbers from the blackboard into the smiley bin. Drag the other numbers into the unhappy bin.

 

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Transum.org

This web site contains over a thousand free mathematical activities for teachers and pupils. Click here to go to the main page which links to all of the resources available.

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Mathematicians are not the people who find Maths easy; they are the people who enjoy how mystifying, puzzling and hard it is. Are you a mathematician?

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"A set of real life savers!!
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"This resource has made a great deal of difference to the standard of starters for all of our lessons. Thank you for being so creative and imaginative."

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Featured Activity

Newsletter

Newsletter

The Transum Newsletter for October 2026 has just been published. Click on the image above to read about the latest developments on this site and try to solve the puzzle of the month. You can read the newsletter online or listen to it by downloading the podcast.

Numeracy

"Numeracy is a proficiency which is developed mainly in Mathematics but also in other subjects. It is more than an ability to do basic arithmetic. It involves developing confidence and competence with numbers and measures. It requires understanding of the number system, a repertoire of mathematical techniques, and an inclination and ability to solve quantitative or spatial problems in a range of contexts. Numeracy also demands understanding of the ways in which data are gathered by counting and measuring, and presented in graphs, diagrams, charts and tables."

Secondary National Strategy, Mathematics at key stage 3

Go Maths

Learning and understanding Mathematics, at every level, requires learner engagement. Mathematics is not a spectator sport. Sometimes traditional teaching fails to actively involve students. One way to address the problem is through the use of interactive activities and this web site provides many of those. The Go Maths main page links to more activities designed for students in upper Secondary/High school.

Teachers

If you found this activity useful don't forget to record it in your scheme of work or learning management system. The short URL, ready to be copied and pasted, is as follows:

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