Subitze

Subi-what?

Subitize.

That's the ability to instantly recognize the number of objects in a small set or arrangement without counting.

It's being able to instantly know the number of dots on a die...

or a domino...

Or for me, the number of cookies on a plate...mmm....6.

It's a developmental prerequisite to counting, and many kindergartners come to school without this skill. So it's essential for us to teach it!

If you're interested in the research behind this concept, here's an excellent article by Douglas H. Clements:

Subitizing: What is it? Why Teach it?

Teaching it is easy! The easiest way is just to flash dot cards and have the kids quickly call out the number. Here's something I put together...a quick powerpoint with dot arrangements. I flash each slide for just a few seconds. Most of the time, I just have the kids call out the number, but sometimes, I have them write the number on dry-erase boards or create the same pattern on their tables with counters.

Download How Many Dots

There are also numerous games you can play with dot cards. The absolute best resource I have found is:

BRAVO to the Winnipeg School Division--I have used the activities in this book for years now. It is filled with SO MANY dot card actvities--and even has the dot cards in it. (And five and tens frame activities, as well.) Did I mention that it was free? So go grab it--NOW! (Click on the image.)

Interestingly enough, the word is pronounced soobitize--with a long u. One would think it was a short u, as in substitute teacher or submarine sandwich. But noooo... it's a long u like tuba-tize.

Now, go use it in a conversation with your principal. He or she will think you're really smart.

Happy Friday!

Comments

[Carolyn Kisloski]

Kathryn, I have to tell you how much I LOVE your blog. I could spend hours here. You have so many fabulous ideas. Thanks so much for sharing your gifts! :)
Carolyn
Kindergarten: Holding Hands and Sticking Together

[Camille]

Thank you for all the great resources!! I am going to be busy checking these out! Another tool is the app Subitize Tree. I used it during whole group math time by putting my iPad under my document camera. I think it is $2.99.
Camille

[Kathleen P]

Fantastic Resource! Thanks for sharing!
Kathleen
Growing Kinders

[Michelle Cooper]

I'm afraid this is a dumb question...but when I open your slide show in Power Point I'm unable to save it. Do you know what I'm doing wrong? Love this slide show and want to include it in my math instruction this year:-)
Michelle
[email protected]

[D]

Thanks so much! Do you use a rekenrek in your room? I just got one and need ideas to effectively use it. Holly Rose

[Rebecca Stilz]

I just attended the Singapore math conference on Vegas and this is so aligned with what all the speakers were saying! Thank you so much for the resources!!! These are great!
Rebecca
[email protected]

[Crystal Young]

Thanks so much for sharing the resources. They are really usefully. I have a suggestion though, I think it would be great to have a blank slide in between the dot patterns. That way you can flash it fast, go to blank screen and then have the kids write the number or show the same dot pattern (which by the way, I think is an excellent idea and extends the lesson perfectly.) And I too can't save the ppt. You're the best!

[Amy]

Thank you so much for sharing your resources!

[Olga Q.]

Love all your ideas! Thank you for sharing. Can someone tell us how to open the "How Many Dots" powerpoint. I tried and even tried extracting the file and everytime I try, I get HTML codes.

[Olga Q]

Here's help for the powerpoints that won't save or open up correctly.
1. Right Click link 2. Save target as.. 3. add (.ppt) to title of ppt and save file 4. Open file as a ppowerpoint

[Kathryn]

Thanks for the tip, Olga. I tried to upload ot as a presentation for people that don't have PowerPoint, but clearly that was an epic fail. I will try to fix it tomorrow!

[debbie]

Kindergarten teacher for 26 years and still loving the little ones. Thanks so much for sharing and teaching me a new idea.

[Renai]

I can't get the subitising dot card book to work. It looks like the link has been removed. Does anyone happen to have it saved? If you can email me a copy to [email protected] I would be so appreciative! :)

[Tammi Myers]

Your link for the Winnepeg (Sp) dot cards/ten frames activity comes up 404. But I found it at http://www.google.com/url?sa=t&rct=j&q=dot+card+and+ten+frame+activities&source=web&cd=2&ved=0CCYQFjAB&url=https%3A%2F%2Fi-9490-directors.wikispaces.com%2Ffile%2Fview%2FEarly%2BNumeracy%2BResources.pdf&ei=x8Y9VKnqJ8PJgwTak4DwBg&usg=AFQjCNE_aiYxmlPo3SOUFbA7aRjGBKSfnQ&sig2=imTRWQUlpmoic2lt-l0c5Q&bvm=bv.77412846,d.eXY&cad=rja