Many years ago, I was invited to work at Glendale School in Glasgow. We were having a particular focus on maths outdoors. The whole point of maths outside is that it is real and relies on practical activities. Often these can be quite revealing in terms of what children do and don’t know.

For example, in this activity we challenged groups of children to make mathematical pictures using 20 objects. Each group had an “imported” material such as sticks, shells or cobbles. They had to count out 20 of these.

Then the children had to search their urban playground for other items which could be added to the picture such as these twigs and leaves. This is a useful trick in quite barren outdoor spaces. Import some natural materials to kickstart but encourage children to look around – often even little leaves, blades of grass and bits of stone can be found.

In the photo below, one child spent a careful few minutes ensuring that each wooden disc had a dandelion inserted into each drilled hole.

However, if you do a careful count, you will find that not every group was able to accurately count out 20 objects. It would seem that this sort of simple task somehow doesn’t happen as much as you would expect. (Check the super accurate example below, though). This is why young children need lots and lots of practical experiences linked to their interests that involve counting different objects in different ways. There are many skills involved.

Also, there is a surprising amount of cooperation required for a group to collectively count 20 of an object, especially when everyone is running to find stones, twigs, flowers, etc. All-in-all it’s a quite a challenging task. The children really did enjoy it and we ended up by seeing if 20 children could fit inside the largest picture – a den!

Middleton Park Primary School made a video of a variation on this blog post – please watch, enjoy and use as inspiration to adapt these blog posts according to the needs of children in your class.

The number 20 – outdoors! from Middleton Park School on Vimeo.

This blog post first appeared in May 2013.