Day 28 - Subtraction

Good morning, kindergarten! Today is Thursday, April 30th , and before we begin, I want to remind you that, in addition to doing this lesson, you should be making sure to log into Raz-Kids for at least fifteen minutes today. The kindergarten teachers can’t wait to see all the books you are reading! You should also be practicing math on IXL or Khan Academy.

Today we are going to be practicing subtraction. Many of you have already been practicing addition. With addition, you put numbers together, so your total gets bigger; but when you subtract, you take away, so your total gets smaller. You have less than what you started with. Sometimes, instead of the word subtraction, you might hear the words “minus” or “take away.”

We’re going to practice some subtraction number stories. I’m going to start with four cookies. Now I’m going to take one of these cookies away by eating it. How many cookies do I have left? If we count them, we can see that I have one…two…three cookies. I started with four cookies, took one away, and ended up with three cookies. So, four minus one equals three. (4-1=3)

Now I have six colored pencils. But I don’t need all of them, so I am going to put three of them away. See, I’m taking away one…two…three. Now let’s count the colored pencils that I have left: one, two, three. Remember, I started with six colored pencils, I subtracted, or took away, three of them, and I ended up with three colored pencils. So, six minus three equals three. (6-3=3)

Do you see how I’m using real objects to practice all these story problems? You can do the same thing at your house! Let’s try one more together. Here I have five books. But I don’t need all of them right now, so I’m going to put four of them away. I am subtracting, or taking away, four books. Now I only have one book left. I started with five books, took away four of them, and ended up with one book. Five minus four equals one. (5-4=1)

Remember, when we practice subtraction problems, we always start with the biggest number. That’s our whole. Then, when we subtract, we take some away, which means that we end up with fewer than we started with. Subtraction means to separate, or to take away. Check out this Jack Hartmann video for more fun subtraction stories! https://www.youtube.com/watch?v=pwQKugrFmJQ

We’ve been practicing subtraction problems using real objects. At home today, I want you to make up your own subtraction problems using things around your house. Then, after you have practiced with real objects, I want you to draw a picture of two of your subtraction story problems. It should look something like this. I took a piece of paper and folded it in half. Then, I did one problem on the top and one problem on the bottom. On the top is the story problem I showed you about the cookies. I drew these four circles to show my four cookies, and then I drew an “x” over one of them because I ate one. Now you can see, there is one cookie crossed out and three cookies are not crossed out. At the bottom of my picture, I wrote out the number sentence. 4-1=3.

On this bottom picture, I drew the story problem about books. First, I drew five books because that’s how many books I started with. Then, I crossed out four of the books because I put them away, so I have to take away four books. There is one book left. At the bottom of this picture, I write the number sentence that goes with it: 5-4=1

Now it’s your turn to try on your own. Make sure to send two number story pictures to your teacher. We can’t wait to see all your hard work!