You may have heard your child’s teacher nonchalantly say that a specific activity helps children develop one-to-one correspondence. Or, maybe in a conference a teacher has told you your child needs to work on one-to-one correspondence. But what exactly is one-to-one correspondence and why is it so important?

One to one correspondence is the ability to match each part of one set to an equal numbers of another set. For example, matching up baby animals with their parent is showing one to one correspondence—each baby matches up to one parent.

One to one correspondence is extremely important when it comes to number sense. Your child may recognize and recite the numbers 1-10, but do they understand that the number 7 represents seven items? One-to-one correspondence activities help your child eventually grasp the concept that each number represents a set quantity.



Activities to promote one to one correspondence.

1. Ice Cube Tray Matching
Supplies: ice cube tray, 12 marbles (or however many individual ice cube squares there are)

Directions: Have your child place one marble in each individual ice cube square. Let them do the activity without any help from you. Only step in if they put more than one marble in each square, and then gently remind them to put one marble per square.

Variations: The ideas for this activity are pretty open-ended. Ideas for counters include: dried pasta, dried beans, pom poms, small rubber animals, buttons, rocks, acorns, coins, small shapes cut out of construction paper, beads, colored lids from fruit pouches, and rubber bands. In lieu of an ice cube tray you can use and empty egg carton.

2. Cups and Straws
Supplies: approximately 10 cups (paper, plastic, or whatever kind you have on hand), straws (one per cup)

Directions: Line the cups up. Your child will put one straw in each cup.

Variations: Instead of straws you could use fake or real flowers, ping pong balls, bean bags, or small toys.

3. Sock Matching
Supplies: Dolls, baby socks (enough for each baby to have a pair)

Directions: Your child will put one sock on each of the dolls feet. Bonus: this is working on a life skill and fine motor skills, too!

4. Clothespin Letter Matching
Supplies: 26 Clothespins, 13 index cards

Directions: Cut each index card in half. Write the letters a-z (lowercase) on each card and each clothespin. Place the cards in one basket or pile and the clothespins in another basket or pile. Your child will match up the lower case “a” clothespin with the lower case “a” card by clipping the pin to the card. This is activity is also working on fine motor skills and early literacy skills.

5. Clothespin Number Matching
Supplies: 10 index cards, lots of clothespins

Directions: Write the numbers 1-10 on the index cards. Near the edge of the card, draw a corresponding circle. For example, on the #1 card you will draw a circle the size of a quarter close enough to the edge so that a clothespin can be clipped onto the circle. Repeat with the other cards.

Note: if you want your child to clip all the cards at the same time you will need 55 clips.

Variations: Instead of using clothespins you could set out counters for your child. Refer to the first activity for a list of ideas for counters.

If you change up the counters and way you do the above activities your child will not get bored with one to one correspondence activities; in fact, you will probably see them begin to incorporate one to one correspondenc activities in their everyday play.