SWBAT compare the lengths of two or more objects to determine which object is longer, shorter, or if they are the same.

Comparing lengths assists first graders in developing concepts of measurement and standard units. This lesson will have my students compare everyday classroom objects for practice.

5 minutes

This lesson is the fourth in a series on measurement and builds a foundation for students later in Third Grade to study area. First Graders must understand that measurement relies on accuracy and standard units are necessary. I will have a discussion with my students about measurement. I want to know do they know what it is and if they do, what kind of experiences have they had with it. My goal will be to help them identify:

- to measure something you have to follow a specific procedure
- when you are measuring you have to begin at a starting point and not just pick a spot
- Lined up means the ends must be matching.

The goal of my discussion is for my students to understand measuring is a precise process and very specific actions must occur for the answer to be accurate.

10 minutes

I will have students use new, non-sharpened pencils to compare measurements throughout the room. I am using non-sharpened pencils so that every student has the same standard length to measure with. This is known as a "length unit" with Common Core, and I will use that term when speaking to my students.

*Students, I will count to 3 and then you can stand up, walk to an object that is shorter than your pencil. *

I will encourage using the terms longer and shorter. Also, to use the statement; Ex. My pencil is longer than the pencil sharpener. Students will have a seat, turn to their neighbor, and share what they found. Then I will select 5 random students to ask, "How do you know?"

*Students I will count to 3 and then you can stand up, walk to an object that is longer than your pencil.*

Again, I will encourage them to use the statement; Ex. My pencil is shorter than the rug. Students will return to their seats and again share with their neighbor what they discovered. Again, I will select 5 random students to ask, "How do you know?"

It is important to ask the "how" questions because it forces students to explain their ideas and increase their critical thinking. These explanations will also help my lower students make more connections.

15 minutes

I will pass out construction paper and have students trace their shoe and then cut it out. They will use this as their length unit to do some measuring. My First Graders need to develop knowledge that different units can be used to measure items. They do not have to actually use rulers at this age level, rather they are building foundational knowledge that using varying units to measure items will result in different answers (though the object stays the same length because it's the *unit* that is changing). (1.MD.A.2). Students will begin to identify this idea with multiple experiences with multiple units especially if measuring the same item with different units.

Students will use the shoe print length unit and the worksheet in the resource section, to walk around the room and compare sizes of different objects. I will ask them to draw a picture and write the name of each object measured on their worksheet.

This activity will require my students to express and explain their thoughts related to measuring and comparing the lengths of objects. Being able to organize their thoughts and clearly explain what they are thinking is a core skill for First Graders to develop. (MP3). Watch as my students are measuring with their paper feet and view a completed work pic.

2 minutes

I want to have a discussion with my students about measurement and comparison. I will line up 1 lincoln log, 5 unifix cubes tower, and 2 legos. I will ask my students:

*Which one is longer?*

The answer will be the lincoln log, but I am curious if anyone will think the 5 unifix cubes is longer than the log because of the quantity. There is 5 cubes and only 1 lincoln log.

I will lay these items out on my table by the door and ask students to look as we exit for our restroom break and we will discuss it when we come back in.

Some questions I might propose:

*Which one was shorter?*

*Which one was longer?*

*Why or why not is the unifix cubes shorter than the lincoln log?*

*Why or why not is the lincoln log longer than any of them?*

Watch our discussion about comparing the cubes and logs.