Comparing Objects by Length

Lesson Plan - Get It!

Audio:

Tall is a word we use to compare lengths, or how long something is.

Since you want the person who is the longest to reach up and get those cookies, you want the tallest person.

• Why wouldn't you want the shortest person to try and get them?

Short is another word we use to compare lengths.

1. Go into your room and see if you can find your tallest stuffed animal, doll, or action figure.
2. Now, hunt for the shortest one.

• How did you know which one was the tallest?
• How did you know which one was the shortest?

Great job! You just compared your toys by length!

Length is the distance from one end to the other end.

For example, the red line is the length of this puzzle piece:

Different puzzle pieces have different lengths.

For example, these two puzzle pieces have different lengths:

• How were you able to tell which puzzle piece was longer or shorter?

I bet you used your eyes to compare the two puzzle pieces!

You can also measure the lengths! Sometimes you will use rulers, tape measures, or meter sticks to measure lengths.

• But did you know you can use whatever unit you want to measure lengths in order to compare objects!

Let's use ants! Ants are smaller than puzzle pieces, so that will be a good unit of measurement to find these lengths:

When finding the measurement of an object, we make sure to line the unit up end-to-end without overlapping.

For this example, the ants are lined up end-to-end and the ants are not overlapping.

We can then find the lengths. The blue puzzle piece is 3 ½ ants long and the green puzzle piece is 2 ants long. We know that 3 ½ is a larger number than 2.

This proves the blue puzzle piece is longer than the green puzzle piece because it has the greater measurement!

To learn more about measuring and comparing lengths, watch Measuring! | Mini Math Movies | Scratch Garden:

• Is there a word you didn't know in the video?
• What was it? What do you think it means?

• If you knew all of them, pick one word and share what it means to you with your teacher.

Now, continue on to the Got It? section to go outside and measure some things!