Primary Type: Lesson Plan
Status: Published
This is a resource from CPALMS (www.cpalms.org) where all educators go for bright ideas!
Resource ID#: 49739
Oh My! Meters or Centimeters?
This lesson is designed to teach students how to use rulers to measure centimeters. They will also learn how to use a meter stick to measure
centimeters and multiple meters at once. Additionally, they will be able to decide whether they should use meters or centimeters when measuring an
object, based on it's overall size, and explain their decision.
Subject(s): Mathematics
Grade Level(s): 2
Intended Audience: Educators
Suggested Technology: Document Camera, Microsoft
Office
Instructional Time: 2 Hour(s)
Freely Available: Yes
Keywords: measurement, meter stick, meter, centimeter, comparing size, measure, ruler
Instructional Design Framework(s): Cooperative Learning
Resource Collection: CPALMS Lesson Plan Development Initiative
LESSON CONTENT
Lesson Plan Template: General Lesson Plan
Learning Objectives: What should students know and be able to do as a result of this lesson?
As a result of this lesson, the students will be able to judge whether they should use centimeters or meters to measure an object based on it's size.
They will also be able to relate how many centimeters (100) create a meter by counting by 10's. They will also recognize that meters and centimeters are standard
units of measure under the metric system.
Prior Knowledge: What prior knowledge should students have for this lesson?
The students should understand that a meter is much longer than a centimeter. They are also able to notice when an object is shorter or longer than another
object.
In first grade, they would have measured objects using whole units (like we are going to do with the unit centimeter squares). In first grade they also should have
learned not to gap or overlap the units.
From our previous lesson, they should know that you need to line up the 0 of the meter stick with the end of the object they are measuring.
Guiding Questions: What are the guiding questions for this lesson?
1. How does this ruler or meter stick help you measure accurately? (I place what I am measuring end to end and measure using the correct units.)
2. How did you decide which tool to use? (Centimeters are smaller than meters, so for small objects I use centimeters and for large objects I use meters.)
3. How can you support that your answer is correct? (When I'm measuring, I make sure to align the ends of the object and the measuring tool.)
4. Are meters and centimeters customary or metric units? (metric)
Teaching Phase: How will the teacher present the concept or skill to students?
I recommend putting students into desk groupings of 3 or 4. You may need to group the students according to skill level, behavioral needs, or interests, etc. This is at
the teacher's discretion.
1. "First, let's look back at our standard units of standard measurement. Are meters and centimeters customary or metric units?"
Look at standard measurement chart (metric units).
page 1 of 4 2. "Before we start using the actual tools, I would like to give you a handout that I hope will help you better understand centimeters and meters."
At this time, pass out meter cm example.
"If you look at this paper, the little cubes represent centimeters, and the big rectangle represents a meter. This is just a picture of a meter stick, not a real one.
This one is much smaller than a real meter stick. Can anyone estimate how many centimeters are in a meter?" (100 centimeters in 1 meter.)
"How does this picture represent that there are 100 centimeters in 1 meter? Cent means 100, just like there are 100 cents in a dollar."
3. Next on the document camera (doc-cam), label the big rectangle "1 meter." Point an arrow to the little cubes and label them "100 centimeters."
"Now that we have our paper filled in, let's look at this visually so that you can understand it better. I have these neat little unit cubes. Let's see how long one
measures."
Put the ruler on the doc-cam and set the unit cube, so the students can read the measurement (1 cm).
4. "Now, we are going to use an old trick that we know to help us."
At this point, you will want a large clean table to work on, or use the middle of the floor. Start by laying out 10 unit centimeter cubes along the meter stick starting
at zero. Once you get to 10 centimeters, have the students stop and think about this.
"Is there a way that we can skip count to get from 0 to 10, and then to 20? Right now, we went from zero centimeters and zero cubes to 10 centimeters and 10
cubes. If we count by 10s, we can tell how many centimeters there are in 1 meter!"
Wishful student response: "We need to skip count by 10s until we get to 100."
Guided Practice: What activities or exercises will the students complete with teacher guidance?
Give a ruler showing inches and centimeters to each student. Ask a student to explain the difference in the sides. Make sure they are using the centimeters side. Next,
give a A) cardboard bookmark or a B) lollipop to each student. After you show students how to measure centimeters, have each student measure their bookmark or
lollipop. *Note: Make sure that all classroom examples are of equal length.
1. "Please measure how many centimeters long your bookmark is. Compare this with your table group. Write the group's final measurement on the white-board. Make
sure to label your measurement 'cm'."
2. "Next, we are going to measure how many bookmarks/lollipops it takes to reach 1 meter."
Each group needs a meter stick and enough bookmarks or lollipops to reach 1 meter. If supplies are limited, you can have 2 or 3 groups within the class group
together and share/investigate together.
"Once your group decides how may bookmarks/lollipops it takes to reach one meter, write it on the white board and ask the teacher to check it."
3. Review how to measure the bookmark/lollipop on the document camera for the students and how to measure the meter using bookmarks/lollipops.
4. "Now I am going to teach you more about using a meter stick. Remember, 1 meter is 100 centimeters. Right now, let's look around the room for things that look
like they are 1 meter long. I see that the window ledge looks just short of one meter. Would this be less than or more than 100 centimeters?"
(less than, because it is not quite 1 meter. You need a whole meter for 100 centimeters.)
5. MODEL THIS BEFORE STUDENTS DO:
"What if I have to measure more than 1 meter at once? How can I do that? First, lay down the meter stick and make sure your ends/edges are straight. Next, use a
pencil to mark where the 1st meter ends. Pick up the meter stick and start using it to measure again at your 1 meter pencil mark." (Repeat the process for
additional meters.)
6. Review results as a whole-group discussion. Students should answer the following questions:
"How does this tool help you measure accurately?" (I place end to end and measure using the correct units.)
"How did you decide which tool to use?" (Centimeters are smaller than meters, so for small objects I use centimeters and for large objects I use meters.)
"How can you support that your answer is correct?" (When I'm measuring, I make sure to align the ends of the object and the measuring tool.)
ACTIVITY: measuring with a meter stick.doc
Independent Practice: What activities or exercises will students complete to reinforce the concepts and skills developed in the
lesson?
1. The independent practice will be done in groups of 2. I recommend grouping students by ability levels, behavioral needs, or however you see the best fit. If you
have a student who is struggling, you may want to partner him or her with a student who seems more fluent with the skill. However, watch to make sure that the
struggling student is participating and not just copying answers. You can assign students to groups based on the results of previous formative assessments.
page 2 of 4 2. While in groups, the students will use rulers with centimeters and meter sticks to measure large paper clips and tables. (The tables need to be at least 1 meter long
and have straight edges.) Use the following link for students to record their responses to the practice: table vs. paper clip
"Now that you have measured centimeters and meters on your own, I am going to challenge you to measure 2 items in this classroom by using a ruler with
centimeters and a meter stick. The 2 items that you will be measuring are paper clips and these tables (show students which ones you want them to measure)."
While students are working, you should make sure that everyone is doing the activity. For groups who finish early, see lesson extensions. Before you let them do a
lesson extension, make sure that they have answered all 4 questions on the table vs. paper clip work sheet and turned it in to you.
Closure: How will the teacher assist students in organizing the knowledge gained in the lesson?
1. Closing questions: I recommend doing this whole group.
"Why did you decide to measure the paper clips using centimeters? Why was it better for us to use meters to measure the tables instead of centimeters?"
2. "What other objects do you see in the room that you could measure with centimeters? What objects should we use meters to measure?"
Why? Try to keep this discussion going until everyone has a chance to tell you one item. You may want to take notes on students' responses to help with future
lessons as a formative assessment.
Summative Assessment
Summative assessment
Please note that you need several blue pieces of yarn that measure 1 meter and several red pieces of yarn that measure 3 meters.
Pictures on Summative assessment are from http://openclipart.org/
Formative Assessment
1. The teacher will make observations while the students are working on measuring the paper clips and tables. Make sure that the unit centimeter cubes are touching
each other when the students are measuring (no gaps in between).
2. For additional assessments, you will collect their data sheets from this project to review who understands/does not understand how to measure using centimeters
or meters.
The teacher will use this information to adjust instruction to meet the needs of the students.
Feedback to Students
As the students are working on measuring the tables and paper clips, make sure that they are naming/labeling the centimeters and meters accurately. You may
need to show some of them how to keep the unit centimeter cubes straight and touching each other. If they are struggling with using too many cubes, you can
show them how to count the centimeters on the meter stick.
Ask guiding questions to assist the students in their concept development, such as:
Why should the cubes be touching and side by side?
Why should the cube begin at 0 on the measuring tool?
Where on the measuring tool would you read the length of the item?
ACCOMMODATIONS & RECOMMENDATIONS
Accommodations:
Make sure that struggling students understand to use the centimeters side of the ruler, not inches. Remind them to look for the cm abbreviation for centimeter and
that the centimeter numbers are closer together than the inches.
For students that struggle with fine motor skills, you might need to help them set the unit centimeter blocks in place without having any gaps or overlaps. They may
also need something to push the cubes up against, such as a heavy text book.
Extensions: As a lesson extension, students who have a firm grasp on the concept can measure the same items (paper clips, yarn strings, tables, etc.) using inches
or yards. They can then compare how the numbers are different, noting that it takes more centimeters than inches to measure the same object.
Suggested Technology: Document Camera, Microsoft Office
Special Materials Needed:
several boxes of large paper clips
several boxes of small paper clips
blue yarn (1 meter long) and red yarn (3 meters long)
large tables in the classroom (1 meter or longer)
unit cubes that measure 1 centimeter
meter sticks
rulers with centimeters (1 for each student)
1 book mark for each student (preferably all the same size). You can substitute this with lollipops if they are more accessible.
connecting cubes (cubes that snap together)
Further Recommendations:
Make sure that you have enough red and blue yarn cut ahead of time before the Summative assessment.
During clean up, make sure the students check the floors and inside of desks for any unit cubes that may have traveled.
You will also want to make sure that students understand that we will be using the centimeter side of the ruler, not inches.
Additional Information/Instructions
By Author/Submitter
page 3 of 4 This resource is likely to support student engagement in the following the Mathematical Practice: MAFS.K12.MP.5.1: Use appropriate tools strategically.
SOURCE AND ACCESS INFORMATION
Contributed by: Abi kosa
Name of Author/Source: Abi kosa
District/Organization of Contributor(s): Brevard
Is this Resource freely Available? Yes
Access Privileges: Public
License: CPALMS License - no distribution - non commercial
Related Standards
Name
MAFS.2.MD.1.1:
Description
Measure the length of an object to the nearest inch, foot, centimeter, or meter by selecting and using appropriate
tools such as rulers, yardsticks, meter sticks, and measuring tapes.
page 4 of 4