SWBAT measure lengths using inch tiles and order them from shortest to longest/longest to shortest.

Watch out for that mouse! Students practice nonstandard measurement by measuring colorful mouse tails, and then putting them in order from shortest to longest or longest to shortest.

10 minutes

**CCSS Context:**

In this lesson, students tackle misconceptions about measurement head on. They look at ways I incorrectly measured a mouse tail and decide if that is correct or incorrect. The misconceptions I highlight are aligned to the measurement standard for first grade (1.MD.A2)-no gaps, same unit repeated, measure from end to end. Students end the lesson by putting the mouse tails in order with a partner, allowing students to practice 1.MD.A1, ordering lengths.

**Read Aloud:** Every first grader I have ever taught loves the tale: The Little Mouse, the Red-Ripe Strawberry and the Big, Hungry Bear. This is a great way to get kids invested in the theme of the lesson while also incorporating high quality literature into your math block. This book is a F&P level I, so it is accessible to first graders to read along with at this point in the year. You can show the read aloud version from this link.

**Objective: **Your thinking job today is: How can I measure this object using inch tiles? How can I put the objects in order?

15 minutes

I'll present a picture of a mouse on my anchor chart without a tail. I'll have a yarn tail that I'll tape on to the end of the mouse tail in a second, showing how I make sure the tail is nice and straight before I start measuring.

**Present problem: Here is my mouse, but I am unsure how long his tail is! I am going to measure with these post it notes.**

*Post it notes ensure that everyone can see, and that you aren't trying to hold paperclips against chart paper!*

**Nonexamples: **I'll model measuring it a few times incorrectly. After each time, I'll ask: What was my mistake?

1. First nonexample: Post its start on the mouse.

2. Second Nonexample: Post its have gaps between them.

3. Third Nonexample: Post its cover up the tail so we can't see it.

4. Fourth Nonexample: Post its go around the mouse.

**Partner talk: Everyone keeps telling me I am doing it wrong! Tell your partner how I should do it so you can teach me in a second!**

10 minutes

This section emphasizes that measurement requires precision. This is aligned to MP6, Attend to precision.

You discussed with a partner how I should have measured the tail. Now I need you to teach me how to do so!

**Guiding Questions:**

- Where will I put my first post-it if I only want to measure the tail?
*This question is tricky because we don't want to include the mouse, I'll feign confusion and start at the mouse so students correct me.*

- Where will I stop my post its?

- Can I leave spaces between my post its? Why not?

- Can I put my post its on top of my line?
- I'll emphasize here that if you can't see the line, you don't know when to stop measuring. We have to keep our units right under the line so we know when to stop measuring.

I charted all of the things student told me we needed to do to measure the tail. **See attached Class Chart for our list! **And then had a child come up and measure the tail correctly. Watch the attached Modeling Measurement video to see how the discussion went!

15 minutes

**Materials:** You can get all of the materials for the Mouse Measurement activity for free at this Love Those Kinders post!

**Teacher prep:** To make this the most fun, print the mouse on cardstock and attach a yarn tail to the end of it. I'm going to make my tail lengths range from 1 tile to 12 tiles long. Each mouse should be labeled A-G.

**Student Work Time Directions:**

1. Student chooses a mouse from their station/table bin.

2. Student measures the length of the mouse tail in inch tiles.

3. Student records the length in inch tiles on the recording sheet and chooses another mouse.

4. When students have completed all of the mice, they get to draw a tail that is a given number of inch tiles long on their paper and draw a mouse to go with it. I'll model this for kids so they know exactly what to do.

** Watch some measurement Partner Work in action!**

12 minutes

**Partner Share:** Take 4 mice from your table bin. With your partners, put them in order from shortest to longest.

- If time...Now switch it to longest to shortest!

**Exit Ticket: **Measuring just a line can be tricky for first graders. This exit ticket insures that they can apply the same practices they used with the mouse tail to a picture. Exit Ticket is attached!