How to Use Subitizing | 5 Different Ways - The Recovering Traditionalist

Have you ever wondered how to use subitizing in your classroom? Subitizing is the ability to instantly recognize ‘how many’. Helping our students develop subitizing isn’t just for Pre-K to second grade. Even third through fifth grade kiddos need to develop subitizing. Stay tuned as we delve into how to use subitizing.

We are going to start off with Pre-K to 2nd grade, and then we’re going to talk about how to do subitizing in 3rd through 5th grade. There’s also a download that you can request underneath this video that summarizes the top five ways for Pre-K to 2nd grade, and the top ways to use subitizing in 3rd through 5th grade, that you could jump right into.

Watch the video or read the summary below. **Skip ahead to 15:25 in the video, if you want to just watch the information for 3rd-5th Grade.**

How to Use Subitizing in Pre-K Through 2nd Grade

#1 Quick Images

Example A

The first thing that you should be doing is quick images, or what I like to call, ‘Flash It’. Basically, you just show a quantity for a limited amount of time. So something like this, then you have it disappear.

The amount of time you keep it up is dependent upon how much experience your students have had. For Pre-K kids, I wouldn’t have it disappear in two seconds. In fact I probably wouldn’t even show this image to Pre-K kids because they should be focusing on numbers and quantities of 0-5. So, it depends on the grade level of your students and their experience with subitizing.

If you’re a second grade teacher and your students have not had much experience with subitizing, then this is a great place to start. But you’ll have to leave this image up longer because students have not built the structure. If they’ve never used Ten Frames before, you can’t expect them to instantly know how much is here. So, instead, you might start with familiar patterns like dice patterns (See example B).

Example B

Students who have experience with dice will be able to subitize this quicker than other kids. When you’re first starting out with dice frames, there will be amounts that some of your kids will instantly know. Typically, it’s 1, 2, and 3. The research from Clements and Sarama says above that, kids will start to develop natural patterns like dice patterns and things that they see. As they go into amounts past 5, they’re doing what’s known as conceptual subitizing. Thats where they are combining small amounts to make the bigger amounts. Even as adults, we can’t subitize 8. Instead, we might see 4 and 4.

So you want to start with small amounts and then gradually work your way up to larger amounts. One of the ways to do that is by doing quick images.

#2: Number Talks or Number Strings.

Example C

Let’s take a look at a Number String that you could do with small amounts. You might start off showing an image like this and just kids how many are there.

The hope is that kids would subitize that amount but, depending on the level of your kids, you may have some who are counting. However, you are crafting these Number Strings using images that are subitizable. They are able to subitize in order to tell how many are there.

Then I might move into one like example D and again ask how many is in the image. I wouldn’t ask how many there are now because some kids might say 7.

Example D

One of cool parts of being able to subitize and doing them in a string is being able to pay attention to the relationships.

Once kids are not just paying attention to counting, and they’re able to know ‘that’s 4 and that’s 3’, then we can start having discussions about what do when you notice that changed. This brings in ideas of 1 and 2 more and 1 and 2 less. There is all kinds of relationship building that you can do once kids can subitize and they’re not spending their time counting. We want to be able to focus on what has changed and the relationships that kids can build. So again, I might show an image like example E, and then right after it show an image like example F. Then I could be able to talk about how many there each time. But also, be able to talk about what has changed, what do you notice, and what kind of relationship do these two images have.

Example E

Example F

If you want to do a Number Talk, they are typically around one problem or one image. Then you have the kids talk about all the different ways that they solved that problem. Or, in this case, when it’s an image, how do you know how many are there? How did you figure it out? You’re asking the kids to talk about the various ways that they figured it out.

Example G

Now, here’s my warning.

Example G is really wonderful for subitizing. However, it’s not very good for doing a Number Talk with. Most kids either just know it. They are just able to subitize that and know its a 6. Or you might get kids who will say, “Well, it’s 5 and 1 more.” You might get kids who talk about, “Well, it’s four less than 10.”

With this image, that’s usually not the number one way that kids will see this. You’ll typically get kids who will say, “Five and 1 more.” Then you’ll ask, “Okay, how else did you see it?” and that’s when you’ll get the really off the wall responses from kids. Thats because you’re asking them how else, and theres no other way that they saw it. So they’ll come up with something that really has no relationship to what’s actually in that image.

If you want to do a Number Talk, you probably need to do one that’s not subitizable. So the same amount like in example H. But it’s not instantaneous. Not even for adults.

Example H

If I hadn’t told you that was the same amount and I had just started with that, you would have figured out how many were in that Ten Frame differently than how I did.

Doing a Number Talk needs to have visual images that allow different ways to see it. When we’re focused on subitizing, we usually just see it and we know. Doing Number Strings, you can use subitizable images to help look at relationships. But when you’re doing a Number Talk, you’re not going to have the whole image be subitizable. There are parts of this image that are subitizable. A lot of kids might see 3 somewhere in this image (I’m not pointing it out because how you saw 3 may be different than how I saw 3). It allows for kids to be able to make their own grouping systems, and that is a big idea.

Oftentimes, in our real life, things are not given to us in a nice Ten Frame with the top filled first and then the bottom row. We have to find ways to group it ourselves. So helping kids to find groupable amounts or subitizable amounts is really helpful when you’re doing Number Talks.

#3: Do Kinesthetic & Auditory Subitizing

You need to remove the visuals from subitizing activities. I know that’s kind of counterintuitive because subitizing seems to be all about visuals and helping kids see quantities, which is a big deal. But we don’t want kids to always have to rely on visuals.

There are lots of things in our life where we aren’t subitizing a visual amount but, instead subitizing something kinesthetic. Like movements or something auditory. You might do activities like, “When I clap three times, I want you to line up for PE.” So you might clap once; then four times; then you might clap twice; and then you might clap three times. They have to be able to hear that audio, and they’re subitizing that. The same is true when kids are doing syllables. When we’re asking kids how many syllables are in something, we are basically asking them to hold that amount in their head. If I have to figure out how many syllables are in my name, Chris-tin-a, maybe I can break that into syllables. However, if they’re not able to subitize, they won’t be able to tell you how many syllables there were.

Think about the auditory pieces in our lives that really require kids to subitize and provide opportunities for kids to do those in your classroom.

#4: Show Non-Examples

Oftentimes when it comes to subitizing, we will just show an amount, and ask how many. With the clapping that I just did, I was combining this idea of using auditory but also doing non-examples. The example I gave was that they could go line up for PE if I clapped three times, but I didn’t clap three times to begin with. I was doing non-examples so that they would have to really pay attention and see the amount or in that case hear it.

Example I

You could do the same thing with flashcards or if you make dot pattern plates. A lot of people do paper plates and then use the little yard sale stickers. You might have plates like example I. You’ve got amounts on there, and you’ll say, “When I show 5,” and show 5 dots on a dotted plate, “you can go line up for PE.” So you might get your dot plates out, and you’re flipping through them, and when you land on the one that’s 5, the kids can go line up.

It’s a quick way for them to get lots of practice. Even though I wasn’t asking how many here or how many here, they were thinking about, “Is that 5?” They’re starting to subitize and say, “No, that’s not 5, that’s 8.” “Nope, that wasn’t 5, that was 4.” They’re doing it themselves without you having to ask every single time. It’s a quick way to get through a lot of subitizing images.

#5: Repeated Exposure to the Structures

The structure that we put in place is leading to helping kids with predictability. But sometimes that’s tough for a group of our kids. Now, there’s no research to back me up on this, just my personal experiences. Kids who have unpredictable lives tend to struggle more with subitizing. We are using a built-in structure that seems obvious to us, and we can rely on that structure to help us out. But for a some of our kids, they are not used to relying on predictability. We’re asking them to trust every time the Ten Frame is presented, and the top row is filled in, it’s 5. If they don’t trust it, they’re going to count every single time.

Every time you hold up a full hand of fingers, you probably have kiddos in your classroom who still count every finger because they have not built the trust. They don’t think it’s predictable. If they don’t have predictable home lives, why would it be predictable? How can they rely on the fact, and trust that every time it’s going to be 5? The answer is continued repeated exposure. Help them use that structure all the time. You’re going to have kids who, after just one or two times of seeing images like this, trust that that top is always going to be 5. You’re also going to have kids where it might take a hundred times counting that top row to get to where they trust it.

I just want to be open about the fact that for some kids, subitizing comes more readily, and other kids need extended exposure to trust the structure that we are putting in front of them. It doesn’t come naturally for them. Prepare to keep that in mind as you work to build subitizing for your Pre-K to second grade kiddos