Measuring begins with direct comparison of two objects. Asking questions such ‘How can we work out which pencil is the longest?’, children can explore strategies such as placing the pencils side by side whilst developing reasoning skills and vocabulary.

They balance objects on scales to find out, say, ‘Which of these shoes is heavier?’ They pour from one container to another to find out and explain clearly how they know, ‘Which of these jugs holds more?’

Children then make the comparisons by measuring each of two objects separately using suitable non-standard uniform units. For example, they count how many blocks they need to match the height of two dolls; they compare the numbers to find out which doll is taller and by how much. They balance each of two shoes against a number of wooden cubes, and fill each of two jugs jug using the same yogurt pot.

Additional User Example

How can we find out which cup holds the most water? Why do you think this will work?

Children can pour water from one cup into the other to say which holds the most and explain their reasoning.

Some children may want to use each cup to fill up a larger container to find that one cup takes more goes to fill the container up than the other cup.

What this might look like in the classroom

Question 1:

You have to collect 1 bean bag and bring it back to the start. The first person to return with one bean bag is the winner. Which one will you collect? Why?

Start and finish here:

Possible Answer 1:

There are 3 bean bags − you have to collect one of them in the quickest possible time. So I want to choose the nearest one.

To find the nearest I will walk from the start to A and count the number of footsteps − being careful not to leave any gaps between each footstep. I will repeat this for each bean bag and then compare the number of footsteps. The fewer the footsteps the nearer the bean bag.

Question 2:

How can we find out who is the tallest person in your class?

Possible Answer 2:

Take some straws. Lie on the floor while your partner places the straws alongside you lining up the straw with your heels and stopping at the top of your head..

Now swap. Compare the number of straws to see who is the tallest.

In this activity it is the explanation and the language of comparison that is important.

It is also important for the children to realise that they need to start and finish in the same place each time.

Taking this mathematics further

Research a history of measurement. In particular, how did the Romans use ‘body measures’.

Making connections

Young children use a variety of objects including body parts such as footsteps, hand spans, and digits to quantify the size of objects such as the size of a desk or the size of their book.

If 2 things need to be compared however, there is a need to develop uniformity. For example, if you want to compare the distance between two objects with your hand span, will it work if two children use their handspans?

Through experimentation of this kind pupils come to realise that if they use one person’s hand to compare two things then this will give them a good estimate because they are comparing the same non−standard unit of measurement.

If better accuracy is required then a smaller unit of measurement may be needed, this may lead to a standard measure, such as the centimetre, being used.