Making 100


Pupils write out the digits 1 to 10 like this:

1   2   3   4   5   6   7   8   9   10

The aim is to create an expression that equals 100 by putting as many + – X and / signs between the digits as they like. You might like to demo one like this:

1    2   3 + 4   5   6  X 7 / 8 – 9 = 123 + 456 X 7 / 8 – 9 = 513

Obviously this one is too high but it does illustrate the method. You can decide whether the pupils must use BODMAS or not (I’d suggest they do!) and whether they are allowed to put brackets in as well.

There are many solutions and you might like to post them in the comments section below when you find them!

Thanks to Cat for this engaging little starter. It might make a brilliant homework too!

Have fun!

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Introducing algebra- consecutive numbers addition puzzle


Here’s are really good way of introducing algebra and getting across the idea of what a variable is. The pdf slides that you can use on the interactive white board to run this activity are here.

Start by getting the pupils to draw this diagram in their books:

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Mexican Wave Sequences


A great little game to make sequences fun!

Get the pupils into a horseshoe. Put up an nth term rule on the board. They have to do a mexican wave around the horseshoe but as they stand up they have to shout out the next term in the sequence. The first person is n=1, second person is n=2 etc… See if they can get all the way around the horseshoe without making a mistake. If they do make a mistake they have to start again! Increase the complexity of the nth term rules as you go along!

A great game as it reinforces the idea that the common difference is the coefficient of the n term.

Sorry, I can’t remember who put forward this idea but it is brilliant. Thank you!

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