# One-to-One Correspondence

Updated: May 19, 2021

*This week we are going to explore the topic of one-to-one correspondence. One-to-one correspondence is the ability to connect an object to the corresponding number.*

One to one correspondence is the idea that numbers correspond to specific quantities. For example when playing a game, rolling a dice that lands on number 3 means the child will count 1, 2, 3 and then move 1, 2, 3, spaces on the game board. The number “three” will always be that quantity, no matter what the child is counting. Accurate counting occurs when children assign one number, and only number, to each individual object. One-to-one correspondence is one of the hardest concepts for young children to master because it involves two things: counting and pointing to the object at the same time. This is a skill that comes after rote counting, because children need to understand how to count and before counting by 2's, 3's or 5's (a skill that is often learned in later preschool and early elementary).

Children are often first introduced to one to one correspondence in a natural way. This can occur by playing with toys that require matching one object to one space, such as putting plastic eggs in an egg carton or fitting shapes into a shape puzzle. Other examples children might encounter include: counting money, setting the table (where each person gets one plate, one cup, one napkin, etc), counting a group of people and playing board games.

A great way to test if your child or student understands the the concept of one-to-one correspondence is by laying out a few objects and asking your child or student to count each object to the corresponding number. Once they get better at their counting skills you can add more objects to count so the student/child can practice.

If the student or child’s counting is random then they will need more practice in one-to-one correspondence.

Some activities to practice one-to-one correspondence:

- Throwing objects in a bucket – children can count how many objects they throw into a bucket.

- Sorting and counting objects- Children can sort through different objects, find the similar ones, and count how many are in each group.

Sometimes one-to-one correspondence happens naturally. Take advantage of these opportunities! One-to-one correspondence is not an easy topic but with practice it will become easier to learn!

Prefer to watch instead of read about one-to-one correspondence? View the video below: