(upbeat music) - [Children] Math Mights!

- Hey Math Mights, welcome back.

And if it's your first time, I'm Mrs. Markavich.

And I'm so excited that you're here with me today.

Let's check out our plan for the day.

First, we'll be solving a Mystery Math Mistake, and then we'll measure with different units.

Let's warm up our Math brain with a Mystery Math mistake.

Oh no.

All of the Math Mights have gotten their strategies all mixed up, and I need your help in seeing if we can figure out the answer.

Okay, here is how it's going to work.

I'm going to act out a Math problem with a concept that you're already familiar with.

And you're going to use your magnifying glass to see if you can find my mistake.

Not a real magnifying glass, you can make one out of your hand, like this, and you can be a Math Detective.

And then, you need to make sure that you can explain your reasoning.

Let's take a look at my problem.

I have the problem 48 plus 13.

Well look who came to help.

It's my friend DC, but he's upside down and turned around.

I don't know if his hard hat and mallet are going to work right.

Let's see if we can solve this problem by doing just like DC would, and make a friendly number.

We're going to start off with decomposing the 13.

I'm gonna take the 13 and put two and 11.

And I know that 48 and two make 50.

Let's do that on the Abacus.

I'm going to slide over 10, 20, 30, 40, 45, 46, 47, 48.

Then I'm going to make the 13.

10, 11, 12, 13.

Then, just like DC did, I'm going to decompose the 13 to make two, I'm gonna slide them over, and one.

Now, if I add, I get 50 plus 11 equals 60.

So I think that 48 plus 13 equals 60.

Did you get the same answer?

Well let's see what my friend Addie has to say.

Addie says, "It looks like the 13 was decomposed "into two and 11 "to make the 48 into a 50."

And our friend Holland says, "Hmm, "I know that 50 plus 10 equals 60, "but the problem says 50 plus 11.

"So the answer should be 61."

Great job catching that Math mistake Holland.

Did you catch the same mistake that Holland caught?

Let's help DC fix that on the whiteboard.

This should be easy to fix.

And look at DC.

He got all straightened out, got his hat on right.

So thanks DC for coming back and getting all situated.

We have 50 plus 11, and it doesn't need to be 60.

We need to make it a 61.

Now, we don't have any corrections to make over here, so let's just count it together.

10, 20, 30, 40, 50, 60, and one, is 61.

Great work Math Mights.

Now, it's time for us to head over and check out our I can Statement of the Day.

Our I can Statement of the Day says, "I can measure the same object using different units."

Take a look at this.

What do you notice?

What do you wonder?

Hmm.

I notice, that there were two different colored markers and, it looks like there's some cubes measuring the top marker, and maybe some different cubes measuring the bottom marker.

Let's take a look at what my friends notice and wonder.

Addie says, "I notice, there are cubes "that are different sizes.

"The black marker is six connecting cubes long."

Holland says, "The green marker is 12 small cubes long."

Addie says, "I wonder, are all the markers the same length?"

Holland wonders, "How can the markers be both six and 12."

Those are great notices and wonders girls.

I think we can take a closer look on the whiteboard to see what they're talking about.

You can see on my board, I actually have blue markers.

I didn't have a black or a green marker, but that's okay.

They're still similar.

And I can still measure them with the different units.

On top, you can see that this blue marker is one two, three, four, five, six cubes long.

But then when I looked down here, you can see one two, three, four, five, six, seven, eight, nine, 10, 11, 12.

The blue marker on the bottom is 12 cubes long.

Well how can that be?

I think we need to take a closer look at our cubes, because our markers are the same.

When I look at the cubes, I notice that the yellow cubes are larger than the orange and black cubes.

So even though the markers are the same, the size of our unit is different.

So the marker can be both six cubes long, and it can also be 12 cubes long.

How could we describe the lengths?

Well, we know that if I took this marker and this marker, and I put them together, we can see that both markers are the exact same length.

So when I'm looking at the cubes, I have large cubes and small cubes.

So that's where the difference is.

The markers are exactly the same, it's the size of the cube that I'm using that is different.

So let's count the cubes again.

One, two, three, four, five, six large cubes.

I'm going to put a six here, and then down here, we have one, two, three, four five, six, seven, eight, nine, 10, 11, 12 small cubes.

Since we measured with different units, it's important that you label it.

You label it with large and small so that you know exactly what it is you're measuring, and where to write your answer.

Great work, Math Mights.

Now, I want you to choose three different measurement units.

You can see that I have small paperclips, large paperclips, small cubes and connecting cubes.

If you don't have any of these items where you're at, you can use toothpicks, macaroni noodles, you couldn't use paperclips if you have some, or any item that is the same length that you have a lot of.

Let's take a look at mine.

You can see mine, I have small cubes, small paperclips, and large paperclips.

And here's my line.

Remember, I wanna hear you say, where do I start measuring at?

I think I heard you, the end point.

So let's start with our small cubes.

I'm gonna grab some, and bring them over.

I'm gonna line them up at the end point, just like this.

Ooh, you can tell, that I'm gonna need a lot of small cubes to get to the end of this line.

So let's keep stacking them together, and then once we have them all lined up, we'll count them last.

So I'm going to keep lining them up, just like this, we're getting their Math Mights.

And you can see like we talked about before, there are no gaps or spaces.

Nothing is overlapping each other.

They are pushed together as closely as possible.

Now, we have measured from end point to end point.

So, let's get counting.

One, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 small cubes long.

Let's make sure that we write that up here, so that we don't forget how many we counted, 19 small cubes.

Now, I'm gonna take the small cubes out of the way and put them back up here.

Then I'm gonna head over to the small paper clips.

I'm gonna grab a few paperclips to get started.

Again, starting at that end point, and making sure that they are touching without any gaps or spaces.

I'm going to grab a few extra, and just like we did with our small cubes, we will count them once we get them all lined up from end point to end point.

Ooh, that one got away from me.

Did you see that?

Now, one more should get us there.

And you can see if I straighten them out without any gaps or overlaps.

I have one, two, three, four, five, six, seven.

I have seven small paper clips.

I'm gonna write that up here.

And if you take a quick look back, you can already see that there's a difference between the units that I am using.

The small cubes had 19 and the small paperclips have seven.

We still have one more unit to use.

Let's put the small paperclips back, and grab our large paper clips.

I'm wondering, do you think there will be more large paper clips than cubes and small paperclips?

Or do you think we will use less large paper clips than cubes and small paper clips?

Let's go figure it out together.

I'm gonna grab a few of these guys and start lining them up, like we've done, end point to end point.

And, you can see that I have, that was pretty fast.

I have one, two, three, four large paper clips.

I'm going to write that in there.

And then we're going to talk about it.

Look at this.

I have four large paperclips, seven small paperclips, and 19 small cubes.

You can see that I needed less large paper clips, than small paperclips and small cubes.

That was a lot of fun using all those different objects to measure the length of the line.

I hope that you enjoyed doing this where you're at.

Math Mights, now it's time for us to measure the shoe.

Take a look at this shoe.

What do you notice?

What do you wonder?

Andre measured his teacher's shoe, and said it was 15 connecting cubes long.

Is his measurement accurate?

Why or why not?

Addie says, "Yes!

"Andre used connecting cubes to measure the shoe.

"He used the same size cubes and, "he measured it accurately."

Awesome job Addie.

I noticed that the shoe was measured from end point to end point, and he didn't leave any gaps or spaces.

Look at this shoe.

Jada measured her teacher's shoe, and said it was 12 connecting cubes long.

Is her measurement accurate?

Why or why not?

Take a really close look at that, and let's see what our friend Holland has to say.

Holland says, "No!

"Jada used connecting cubes, "but she has gaps between her units.

"Her measurement is not accurate."

And remember Math Mights, like we talked about earlier, we can't leave any gaps or spaces or we won't have an accurate measurement.

We have another shoe that we're going to check out.

We're going to measure this shoe.

Clare measured her teacher's shoe, and said it was 30 cubes long.

Is her measurement accurate?

Why or why not?

Addie says, "Yes!

"Clare used small cubes to measure.

"She used all the same size cubes.

"Her measurement is accurate."

Great thinking Addie.

I noticed again, that the cubes were lined up from endpoint to endpoint, and there weren't any gaps or spaces, or overlaps.

Great work.

I have one more shoe for us to check out.

Take a look at this one.

Kiran measured his teacher's shoe, and said it was 19 cubes long.

Is his measurement accurate?

Why or why not?

Take a really close look at that shoe, and look at those cubes that he used to measure it with.

Let's see what our friend Holland has to say.

Holland says, "No!

"Kiran use different size cubes, "so he did not get an accurate measurement."

All right Math Mights, let's take a look at that again.

You can see that Kiran used different sized units, and that makes for this to be an inaccurate measurement.

He did a great job of lining up the cubes from end point to end point, but he has to remember to use the same size cubes every time.

Great observations, Addie and Holland.

I'm glad you were here to walk us through this.

Now it's your turn, to measure with different units of measurement.

You could use some of the things that we used today.

Small or large paper clips, or small or large cubes, or anything that you have where you're at.

Maybe you have toothpicks or macaroni noodles.

You can find something that you can measure with.

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

We were able to solve a Mystery Math Mistake, with our friend DC.

And we were able to fix his adding mistake because we were great detectives.

And then, we were able to measure using different units.

We used small and large paper clips, and small and large cubes.

Until I see you next time, kiss your brain.

(upbeat music) (upbeat music) - [Child Voiceover] Sis4teachers.org.

Changing the way you think about Math.

(upbeat music) - [Voiceover] The Michigan Learning Channel, is made possible with funding from the Michigan Department of Education, the state of Michigan, and by viewers like you.

(upbeat music)