Ready to unlock all our resources?

Triangular numbers: handshake investigation

If everyone in a group of people shakes hands with everyone else, the total number of handshakes will always be a triangular number. Is this true or false? Investigate!

Keystage: KS2, Year 6, 11 Plus

Join TheSchoolRun today...

... and instantly access thousands of worksheets, activities and games for your child

Shopping basket

0 items

View basket

Worksheet finder

TheSchoolRun offers parents thousands of printable and interactive worksheets, covering every aspect of the primary curriculum. These are available to our subscribers but you can try a few for free here:

Tutorial finder

In each interactive tutorial, our digital teacher explains the method, shows you examples and then gives you a chance to practise what you've learned. Find out more.

Tutorials are available to TheSchoolRun subscribers only but you can try for free: Learning the 4 times table, Long multiplication and Finding multiples

Learning pack finder

If there is a specific area of learning your child needs support with, our packs offer information, advice and plenty of engaging practical activities. Written by teachers and experts and exclusively available to TheSchoolRun subscribers, learning packs (each 50+ pages long) are fun as well as practice-packed.

JOIN
over 250,000 parents
& get FREE resources and
activities for your child!

Once you sign up, we will create a FREE account for you on the site and email you activities and offers. You can unsubscribe from our mailing list at any time. Please read our privacy policy

Start your 14-day trial

for FREE Click here

How to use TheSchoolRun

Testimonials

Thank you for all your extraordinary materials that have made working with my Year 6 child such a pleasure.

- Yolanda, London

This is an excellent resource, for anybody looking to understand more about the curriculum that your children are studying and add some extra support at home. Highly recommended by a parent of two children who uses this from Reception to Year 4.

- 5-star review on Trustpilot from Anne-Marie Allman

I loved that the 11+ Programme built up each skill slowly but you knew that everything would be covered by the end.

- Christine

We found TheSchoolRun collateral very useful, timely, fun and relevant for our Y6 child. He went on to attain superb SATs results, with all the hard work definitely making a huge difference.

- Neil , Warrington

View more testimonials

Triangular numbers: handshake investigation

DOWNLOAD THIS RESOURCE INSTANTLY with a 14-day FREE trial!

More like this

Join TheSchoolRun today...

Worksheet finder

Tutorial finder

Learning pack finder

DOWNLOAD THIS RESOURCE INSTANTLY
with a 14-day FREE trial!