What is 1:1 Correspondence?
1:1 correspondence is when a child moves past rote counting and is able to count rationally – by assigning one number to each item, in the correct sequence. It means to count objects reliably, one at a time, and give a total value to answer the question ‘how many?’ It can also be called one-to-one counting. For example if you give a child 3 rubber ducks and ask them how many ducks there are? They would be able to physically touch each duck and count that there are 3. A child who has not yet developed one-to-one correspondence may skip over an object, count an object more than once, or not yet see a connection between the number names and the objects.
How Do You Teach 1:1 Correspondence?
You can see now why teaching children HOW to count objects and items is extremely important. Being able to count up to 20 doesn’t necessarily mean anything in real life if you can’t use it for anything! Teaching children how to count with 1:1 correspondence usually begins as early as age 3. Some children will understand what this means through watching you throughout the day. Other children may need to be explicitly taught this skill.
I have found that 1:1 correspondence is a foundation for all the skills that come after it: adding, subtracting, finding one more and less, and lots of other things too. Without 1 to 1 correspondence, all these are a non-starter. When children can count to probably at least 5 by rote, then they are ready to start practicing 1 to 1 correspondence. Many students in my Autism classroom struggled a lot with this concept. So much that I had to create materials and really narrow down how I would teach it. Here are 3 easy ways I came up with to teach 1:1 correspondence:
1. Pass Out Items in Class
This is my favorite life skill to teach throughout the day. I used this method a lot during snack time. I had a snack helper in my class and they would be in charge of handing everyone a napkin and a snack. Therefore, they had to count the students at the table to know how many snacks and napkins to gather. Myself or a paraprofessional would model this for them the first few times, then go around and use hand over hand to touch each student’s shoulder at the table and count. We liked to practice for weeks upon weeks like this until the student may be able to do it independently. You can use this in other ways such as passing out pencils or papers too.
2. File Folder Activities
I created 1:1 Correspondence Math File Folders specifically for my students that struggled with this skill. For these tasks, I wanted my students to gain a really strong understanding of counting to 10. There are actually 15 different activities to practice counting items such as frogs, clouds, apples and penguins. I really love this because I differentiate them to use the file folders 2 different ways. You can put velcro on the back of the number cards for when students will use these file folders for independent work. Then they just count the objects in the picture and find the correct number answer.
Another way that I have used them is to put all of the numbers 1-10 on binder rings so you can flip to the number answer. I tend to use the file folders for direct instruction when I use them this way. Typically, I still do this in small groups of 2-4 students that are working on this math skill or have an IEP goal for it.
3. Count Everyday Objects
This is a strategy that I use to sneak math in during the day when my students least expect it. If you have to go up the stairs to art class, count the stairs as you walk. Have students count their snack items as you pass it out. For example-everyone gets 4 cookies or 10 goldfish for snack. Count items on a page in a book as you read it. Using everyday objects like this to practice 1:1 correspondence will really help students to start to generalize this skill.