(playful music) (sparkles tinkle) (Springling boings) (Value Pak squeaks) (glass squeaks) - [Kids] "Math Mights".

- Welcome Math Mights.

I'm Mrs. Markavich and I'm so excited that you're here with me today.

I have so many great math activities planned for us that I know you're just going to love.

Speaking of math activities, let's check out our plan for the day.

Today, we'll be solving a mystery math mistake and we'll talk about near doubles.

Let's warm up our math brain with a mystery math mistake.

Oh no, all of our Math Mights have gotten their strategies all mixed up.

DC is holding Arbacus' wand?

What is going on here?

Okay, here's how our mystery math mistake is going to work.

One of our "Math Might" characters will be featuring a problem that they're struggling with.

It's your job to find the mistake and help them solve it correctly.

Let's see who needs our help today.

It looks like it's DC.

DC is trying to solve the problem 9 + 5 and it looks like he's decomposed the 5 into 2 and 3.

Let's continue his work on my whiteboard.

So DC took the problem 9 + 5 and he decomposes the 5 into 2 and 3.

Then DC knows that 9 and 2 equal 10 and 10 + 3 = 13.

Hmm, what are you thinking?

Does this look right to you?

Let's see what our friend Fariah thinks.

Fariah says, "DC did decompose 5 correctly into 2 and 3, however, I'm not sure it helped to solve the problem."

Well, let's take a look at what Fariah is telling us.

She's right.

Do you see did decompose the 5 into 2 and 3 correctly, but she's not sure that it helped and that the work is correct.

So we better see what our next friend is saying.

Dawson says, "DC was incorrect.

He needed to decompose 5 into 1 and 4."

Oh, this is a really big mistake.

I think we better take a closer look at this using the double 10 frame mat.

So we're going to put on the top 9 counters, six, seven, eight, and nine.

And then we're going to put 5 counters down here.

Oop.

Now, DC decomposed the 5 into 2 and 3 which means we would put 2 counters up, oh.

Wait a minute, this isn't correct.

I can't put 2 counters in the top 10 frame when there's only 1 space left.

So this must be what Dawson was talking about.

It has to be decomposed into 1 and 4.

So let's pull this back down and take a closer look at that.

I'm gonna move the problem over here to say 9 + 5 and decompose it into 1 and 4.

That means this here, we could put that 1 from down here up there.

That would give us 10 + 4.

10 + 4 would give us the total of 14.

Wow, this is great work, Math Mights.

You definitely know you're becoming mathematicians when you're able to find errors in math and solve them correctly.

Let's check out our "I Can" Statement of the Day.

It says, "I can use near doubles to help me add."

Let's take a look at the slide.

What do you notice?

What do you wonder?

Well, I noticed that there are two 10 frames that are not completely filled in.

So it makes it a little bit hard to find the total.

I wonder what my friends are thinking.

Fariah says, "I notice the top 10 frame has one more counter on it than the bottom 10 frame."

And Dawson wonders, "Can I use the double fact 5 + 5 to solve this problem easier?"

Oh, let's talk about Fariah's notice first.

She says, she notices that the top 10 frame has one more than the bottom 10 frame.

That's a great notice.

And Dawson is wondering, "Can I use the double fact," which would look like this, 5 and 5, "to make solving this problem easier?"

I think that's a great wonder because I was wondering the same thing as Dawson and you know what?

I have a Math Might friend who's really good at doing this.

Do you want to meet him?

(bright music) (squeaks) (zaps) (gibberish) Abracus is a Math Might that lives in Mathville.

Abracus has a magic wand that he uses to zap numbers to change them temporarily.

And then when he is done, he's zaps them back and he does this to help with compensation.

Let's see how Abracus is going to help us today with near doubles.

Let's check out the near doubles with Abracus.

We have the problem 6 + 7 =, hmm.

Let's go ahead and check it out on my whiteboard.

We can solve this together with some help from Abracus.

So I've got 6 + 7 =, hmm.

Let's build it on our double 10 frame mat.

We're going to start with 6 on top, one, two, three, four, five, and six.

Then we're going to put 7 on the bottom, one, two, three, four, five, six, and seven.

I want you to grab your magic wand, just like Abracus.

We are going to zap that 7 together.

Are you ready?

We're going to zap the 7 and take 1 away.

Now, you can see the double of 6 and 6.

To show you how that's done over here, I'm gonna go like this and take 1 away.

Now, I have the double of 6 + 6 and we all know our doubles.

We practice them a lot.

It's a really important skill to know.

You know 6 + 6 = 12.

So we'll write that here.

Now, you're probably saying, "But wait a minute, what about that 1 that we zapped away?"

Are you ready?

We're going to zap it back.

Here we go.

We zapped it back and to show how to record that, we're going to take the 12 plus the 1 that we took away and that will give us 13.

Do you see how that worked?

Do you think we can try it, the same problem, but the other way?

Let's give it a try.

So now this time, we're going to do the same expression, but we are going to zap our 6.

Are you ready?

Get that magic wand out.

Here we go.

We're going to zap the 6 and turn it into a 7.

So that means over here, we're going to add 1 and turn it into 7 and go ahead and tell me that double fact.

7 + 7 = 14.

We'll record that here.

Now, get your magic wand back out because we're going to zap that 7 and turn it back into a 6.

And we're going to bring our 14 down and take that 1 away we added and that's going to give us 13.

Wow, that was great help from Abracus doing near doubles.

Do you think you're ready to try another problem?

This time, let's try near doubles with 8 + 7.

The first thing we'll do is build it on our double 10 frame mat.

We'll put 8 at the top, three, four, five, six, seven, eight, and then we'll put 7 on the bottom, one, two, three, four, five, six, and seven.

Do you remember what to do?

Get that magic wand out.

We're going to zap the 7 first.

So get ready.

We're going to zap that 7 and put another counter there.

So we're going to add 1 so that we have the double fact 8 + 8.

Now, I know, you know your double fact of 8 + 8.

That equals 16.

We'll go ahead and record that over here.

Now, get your magic wand back out and go ahead and zap that counter away.

And this time, we'll take 16, the 1 that we took away, and that's going to give us the answer of 15.

Isn't that cool how that works?

Let's try it the other way.

So we're looking at our double 10 frame mat.

Here's what I want you to do.

We're going to start at the top with the 8 and zap our 8.

Are you ready?

Get your magic wand out.

Here we go.

Zap the 8 and take it away.

So we're going to record it with a - 1.

And now we're going to write our double fact of 7 + 7 which is 14.

Then you're going to need that magic wand where you're going to zap that counter back on there.

So we'll zap it on.

We'll add 1 back on to 14 and that will give us the answer of 15.

Great work with this near double fact.

This time, we're going to try a near double with Abracus doing the problem 9 + 7 =, hmm.

Wait a minute.

This one looks a little bit trickier.

This time, we're going to be adding or subtracting 2.

Are you ready?

Let's give it a try.

I've written out the problem here for us.

We're going to put 9 on top, three, four, five, six, seven, eight, and nine.

We're going to build 7 on the bottom, one, two, three, four, five, six, and seven.

Now, I want you to get your magic wand.

We are going to zap the 9 and we're going to take away 2.

Let's do that now.

Get ready to zap it.

Take away 2.

Now you can see that I have 7 and 7.

So what we're going to do with the 9 is take 2 away, bring down our 7 + 7.

You have to be really good at this double fact by now.

You know that it's 14.

Then we're going to bring our 14 down and you're going to need your magic wand one more time to zap those 2 back up there.

Are you ready?

Zap them back in.

14 + 2 is going to give us the total of 16.

Wow, this is impressive work.

We were able to solve all of these different problems using Abracus' strategy of near doubles.

I know he would be so proud of all of your hard work.

Now, let's see if we can apply that strategy to another game.

It's called Near Doubles Towers.

Here's how it's going to work.

You're going to grab some counting cubes and you're going to create a double.

Here you can see that we've created 4 and 4 as the double.

Then you're going to add 2 more counters to one of the towers to make 6.

Then we're going to write an expression from what we created.

Let's give it a try.

Here you can see my double of 5 and 5.

Then the next thing we want to do is add 2 to one of our towers.

Let's do that now.

So I'm going to add 2 on here like this.

Then we're going to write a problem based on what we made.

So you can see our first tower is 5 plus our second tower, which was 5 and 2 which is 7.

And we know that 5 + 7 = 12.

Did you see how that worked?

Did you see how the 5 and the 5 of the double plus 2 more would give us the 12?

Abracus would be jumping with joy that we were able to use his strategy of near doubles with 1 or 2.

Now, it's your turn to try near doubles with Abracus.

First grade Math Mights, I had so much fun with you today.

We were able to solve a mystery math mistake and help our friend DC.

Then we were able to add near doubles with our magical friend Abracus.

Until I see you next time, I want you to kiss your brain.

(lips smack) (bright music) (playful music) - [Kid 1] Sis4teachers.org.

(transition whooshes) - [Kid 2] Changing the way you think about math.

- [Woman 1] The Michigan Learning Channel is made possible with funding from the Michigan Department of Education, the state of Michigan, and by viewers like you.

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