# What is one to one correspondence in math?

## One to one correspondence. It’s something to do with counting, it’s certainly a bit of a mouthful to say, but what exactly is it? Let’s find out.

One to one correspondence is a skill that young children need to develop in order to learn to count things.

And, it’s an important one.

Let me show you by way of an example (If you have a young child in your life, this scenario may well sound familiar…).

Your preschooler sets about counting something, let’s say the number of stickers they’ve stuck on their piece of paper.

There are 4 stickers on the paper. Your child points to each one in turn and as they point they count: “One…. two…… three….. four, five, SIX, SEVENEIGHTNINE!”

They’ve pointed to 4 objects, but have said all numbers up to 9.

In short, they’re still working on their skills of one to one correspondence.

## What is one to one correspondence in math?

One to one correspondence is the skill of being able to assign one number to one object as you count.

It’s a pretty crucial skill that you need in order to be able to count things accurately.

And it takes a fair bit of practice for little ones.

Think about it for a second.

Not only does a child need to be able to say all the numbers in the correct counting order, but they also need to point to each object at the same time and at the same speed.

Add to this the fact that they must count each object only once, and it’s easy to see why it all takes a bit of practice.

Whilst one to one correspondence is a skill that will come with time, there’s lots that you can do to help your child to master this skill.

Two simple things are:

### 1. Model counting

When you’re doing anything that involves counting, model how you do it.

Demonstrate counting by saying each number slowly and out loud.

As you count, point or touch (or even better move) each object so your child can see that each number you say corresponds to one object.

When you’ve counted the objects, recap everything in one quick sentence. For example: “What number did we get to? 7? So we have 7 blocks! Great job!”

### 2. Lots of counting practice (using objects that your child can pick up and move)

So it may seem obvious, but lots and lots of counting will help your child develop their one to one correspondence skills.

Where possible, do activities using objects that your child can hold and handle such as blocks, pom poms, bean bags, mini erasers or toy cars.

Count the objects into a container so that your child is having to move the object as they say each number in the counting sequence.

We know that young children learn so much by ‘doing’. Saying the number whilst they move an object can be really good for helping them associate one number with one object.