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I looked around the overcrowded classroom. There was that working buzz which so warms the hearts of teachers. Forty-one heads were bent over pieces of paper, pencils in hands, busy working collaboratively on a maths puzzle in pairs and threes.

Why such an oversized class? Why such a crowded room?

This was no ordinary maths lesson. There were 24 children, mostly Years 3 and 4, and there were 17 adults working with them - mothers, fathers, one grandmother and two grandfathers, a classroom assistant and their regular teacher. Every child was working with an adult, and no two adults sat together. Some adults had two children in their group, but no more.

The teacher had put on a similar session two years ago, as part of a twenty-day maths course. Last year she asked me to run the hour-and-a-half session. At first it sounded rather daunting. I had some idea of the level of the children's mathematical ability, but none of their parents' capabilities or expectations. I know that many members of the British public will shrink in fear at the very
mention of the word 'mathematics'. Presented as puzzles and problems they will frequently have a go, but mention numbers, let alone 'geometry' or 'algebra' and nearly everyone has thought of something more pressing to do. This was definitely a "Maths Afternoon" and I wondered how many parents would finally turn up. As it turned out I need not have worried, only those whose work prevented them did
not come.

I presented the puzzles and games and then stood back amazed at the scene. Such enthusiasm, such hard-working minds! I did go round making sure that the puzzle had been understood and giving the occasional hint, but it was hardly necessary. I merely had to judge when to move on to the next activity in conjunction with the class teacher. This is always a difficulty in whole class teaching, as
all teachers know well. One Dad (an artist) was worrying away with a visual problem (rearranging matches) long after the others were involved with some activities with calculators!

I had known that the children would become involved, because children of that age are great at participation. It was the involvement of the parents which was so exciting to watch. Perhaps, with more schools inviting parents to such events, there could be the improvement in the attitude to the subject which the government, and all of us, so desire.

came from a variety of sources, but some can be found in the publication given below. I avoided too much equipment but some can make for more interesting activities. Besides pencil and paper I used headless matches, counters and dice, squared paper, calculators and some photocopies to save time and hassle.

I will give just two activities here. The first is one for calculators, because they have had such a bad press, and are a superlative learning device.

Calculator one hundred

Use only these keys on your calculator:

1 2 3 4 5 6 7 8 9 + =

Make 100 using two 2-figure numbers in ten different ways.

The second is an old favourite of mine, which came to me from David Hale many years ago.

The square cake

There is a square cake, iced on the top and along the sides.

Can you divide it among five people so that they all get equal amounts of both cake and icing?

[First hint: use squared paper. Second hint: use a 5 x 5 square.]

This is subtle problem with a variety of solutions, some a good deal more elegant than others! At least one can be generalised to give a rule for any number of equal divisions of a square cake.

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Many of the puzzles etc can be found in

Numeracy - A whole school approach - Pack 3: Parents, Home and the Community

(Photocopy masters) Pearson Publishing, Cambridge. UK.

http://www.pearson.co.uk

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A version of this article (with some more puzzles) was first published in

Mathematics Teaching No. 166. March 1999

Journal of the ATM (Association of Teachers of Mathematics)

http://www.atm.org.uk/

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About the Author: Jenny Murray lives by the sea in Suffolk. She is a retired primary teacher, ex-college lecturer and primary maths specialist who still spends time in school and who has produced much material for primary teachers, most of it on maths and numeracy. She is a member of the ATM and has written occasional articles for "Math Teaching" for many years.