Okay, I realize the title of this post is very corny, but it got your attention so I can talk about one of my favorite subjects–subitizing. My sister will say that’s Greek to her, so let me put it in simpler terms. When you instantly recognize a quantity without counting, you subitize. For example, if I roll the pair of dice shown here, I instantly recognize the 4 and the 2 without counting.
This is a foundational skill for students. Subitizing is not a new concept. According to Wikipdia the term was first used in 1949. But it seems that recently there’s lots of chatter about subitizing. I was at a professional development session Friday put on by one of the fabulous presenters from Origo, and he listed subitizing as one of the six components of number sense. He went on to say that it was, by far, the MOST important!
I was in the kindergarten classroom of an amazing teacher today. As her kiddos sat in a circle around her, she flashed cards with random dot patterns on them. The kids shouted out the number represented by the dots on each card. As if that weren’t fabulous enough, they went on to volunteer HOW they saw each number. Here’s what I mean. The figure below shows one of the patterns she flashed. Some kids said they saw 2 groups of 3, and they knew that was 6. Another child saw 2 groups of 2 on each side and another group of 2 in the middle. The student explained that 2 + 2 + 2 = 6. Yet another student saw 3 groups of 2, but he saw 2 on the top, 2 in the middle, and 2 on the bottom. How cool is that?
John Van de Walle talks about subitizing in his book Teaching Student-Centered Mathematics: Grades K-3. He provides blackline masters of dot patterns that can be used exactly like I saw being done today. Click here for the blackline masters. I enlarged some of Van de Walle’s cards so they would be easier to use, and you can grab them here.
Thanks for making it to the end of this long post! And now a little reward for sticking with me. I would love for you to follow my blog and visit my TPT store and follow me there as well. If you do that, send me an email, and I will email you either my Numbers to 20 posters or a set of my Operations posters for FREE! Let me know in the email which freebie you want.