Primary Type: Lesson Plan
Status: Published
This is a resource from CPALMS (www.cpalms.org) where all educators go for bright ideas!
Resource ID#: 49719
Make A Mighty Monster: Practice with Area and
Perimeter
In this culminating activity, students will use their knowledge of area and perimeter to create a "Mighty Monster" following specific criteria. Given a
designated area, students will make their monster on centimeter grid paper and calculate both the area and perimeter of each body part, as well as
the combined area and perimeter of the entire figure.
Subject(s): Mathematics
Grade Level(s): 3
Intended Audience: Educators
Suggested Technology: Document Camera, LCD
Projector
Instructional Time: 1 Hour(s)
Freely Available: Yes
Keywords: area, perimeter, mathematical reasoning
Instructional Design Framework(s): Guided Inquiry (Level 3)
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?
Students will be able to clearly distinguish between area and perimeter. Specifically, that by counting unit squares they are finding the measurement of area. By
counting units around the outside of a plane figure they are measuring perimeter.
Students will be able to create a gridded drawing following specified criteria.
Students will be able to add partial measurements of area and perimeter to find a total measurement.
Prior Knowledge: What prior knowledge should students have for this lesson?
Students should have knowledge of how to find the area and perimeter of both squares and rectangles.
Students should know the attributes of both squares and rectangles.
Guiding Questions: What are the guiding questions for this lesson?
1. Do rectangles with the same area also have the same perimeter?
2. Is there anything that made this task difficult for you?
3. When you encountered a difficulty, what mathematical strategy did you use?
4. Are measurements of area and perimeter related? If so, how?
5. Imagine that a student made a monster leg that was 8 square units, but they realize that is too big of an area. Will decreasing the area of the leg affect the
perimeter? Explain.
Teaching Phase: How will the teacher present the concept or skill to students?
HOOK: The teacher will show the following video clip (click to open), show the animated video by clicking the "Step-by-Step" link.
1. Following the video, tell students that they will be using their knowledge of both area and perimeter to create a "Mighty Monster." At this time, provide an example
(click to open) of a monster that you have already created.
2. Using grid paper and either an overhead projector or document camera, model how to create unit squares on grid paper. Emphasize that, with your monster, you
page 1 of 4 are used only straight lines that follow the grid paper.
3. Point out that you have used at least one arm, one leg and one head for your example.
4. Ask students to guide you through the process of finding the area for each section of your monster. For example, ask, "How would I find the area of my
monster's head?" As you elicit answers from students, use a pencil to shade in the area that has just been given. Write the corresponding measurement near the
example. If, for example, the head is correctly identified as having an area of 12 sq. cm., next to the head, write this measurement as: AREA = 12 Sq. Cm.
Emphasize that area is always written as square units because you are measuring how much surface the body part covers.
5. Using the same monster body part, ask students how you would find the perimeter. Using a dark marker, slowly trace around the outside of this body part as
students count the perimeter. Write this measurement near your example as: PERIMETER = ______ cm.
6. On blank centimeter paper, displayed via the document camera, show a monster head with an area of exactly 20 sq. units.
7. Ask students, "Is there a way to draw a head with the exact same area, but having a different shape?"
8. Invite representatives up to the board to create and display figures with an area of 20 sq. units but in a different shape.
9. Invite representatives up to the board to count the perimeter of each figure.
10. Emphasize that plane figures with the same area can have different perimeters.
11. Now, on centimeter grid paper, draw a rectangular plane figure with one missing side. Count the perimeter of the figure, stopping when you come to the missing
side.
12. Ask, "Am I able to find the perimeter of this figure with one side missing?" (Accept answers)
13. Lead students to the understanding that, yes, perimeter of a rectangular plane figure can be measured with a missing side because we know the attributes of a
rectangle (that is, that opposite sides are equal).
Guided Practice: What activities or exercises will the students complete with teacher guidance?
Instruct students that their task is to create a monster of their own meeting all of the following criteria: (You may list these on the board or display on the document
camera.)
Your monster must have at least one head, one arm and one leg.
All monster body parts must be at least one centimeter wide.
There must be two (2) different body parts that have the same area.
The area of your monster must equal a total of exactly 84 square centimeters.
You are to find the area and perimeter of each body part, then find a total perimeter of the complete monster.
1. Distribute centimeter graph paper and instruct students to begin creating their monster.
2. As students are creating their monster, circulate around the room to probe/ask guiding questions.
3. When finished, students should color their monster, carefully cut it out and mount on construction paper.
4. Students should then write the measurements of each section of their monster near that body part. For example, near the head, the student should write both the
area and perimeter.
5. When all body part measurements have been labeled, students should write a total area and perimeter for the entire monster at the bottom of their construction
paper.
As students are creating their monster, the teacher will circulate around the room checking to make sure that students are listing all area measurements in square
units, students are drawing/using only straight lines as they follow the grid, students are following the listed criteria, all area measurements are exactly 84 square
centimeters total.
Independent Practice: What activities or exercises will students complete to reinforce the concepts and skills developed in the
lesson?
1. For homework that evening, have students complete the following assignment:
Draw all possible rectangles that have an area of 24 sq.cm. Find the perimeter of each rectangle you draw.
2. The following day, have students share their rectangles (display on document camera).
3. See which student(s) came up with the most ways to draw a rectangle with an area of 24 sq.cm.
Closure: How will the teacher assist students in organizing the knowledge gained in the lesson?
1. Use Post-It notes to cover up the area and perimeter of each monster. Ask students to switch drawings and have students find both the area and perimeter of
another student's work.
2. As a summarizing activity:
1. Draw two rectangles with an area of 12 sq.cm.
2. Find the perimeter of both.
3. Write one statement describing the relationship between area and perimeter. Possible Sample Statement: Area is the amount of space inside a
plane figure. It is always measured in square units. (When I think of area I think of how much carpet would it take to cover my bedroom floor). Perimeter
measures the outside of a plane figure (I think of a fence surrounding a garden).
Summative Assessment
1. Teacher will use the completed "Mighty Monster" from each student as a Summative assessment.
2. The following day, hand back student creations. On a separate sheet of paper, using their monsters, ask students to write a paragraph, either proving or disproving
the following statement:
All rectangles with the same area will also have the same perimeter.
Students must use specific examples from their "Mighty Monster" to support their contention.
Formative Assessment
The teacher will circulate around the room.
Great value can be gained simply by listening to student conversations as they work.
Listen as students explain how to find both area and perimeter during the demonstration phase of the lesson.
Correct any inconsistencies or misunderstandings.
Feedback to Students
The teacher will monitor and observe as students create their monster.Are students able to clearly distinguish between both measurements (area and
perimeter)?
Throughout the time that students are creating their monster, the teacher should be moving from table to table. Ask probing questions, such as:
How did you determine the perimeter of the monster's head?
What made you decide to make two arms with an area of 10 sq.cm. each?
Explain to me how you decided how big to make the area of the monster's body?
page 2 of 4 Students should be able to verbalize the mathematical operations they are using to construct their monster.
ACCOMMODATIONS & RECOMMENDATIONS
Accommodations: For students having difficulty with, either counting units to find area or counting around the outside of a figure to find perimeter, a number line or
multiplication chart can be provided.
Extensions:
1. As an extension to this lesson, ask students the following questions:
Given a perimeter, how can I find the area?
Is there a rule describing the relationship between area and perimeter? (Accept all reasonable answers.)
2. Sample Extension Problems: Use centimeter graph paper to draw each rectangle.
A rectangle that has a perimeter of:
1. 18 units.
2. 8 units.
3. 20 units.
4. How can I find the area?
Suggested Technology: Document Camera, LCD Projector
Special Materials Needed:
Materials for the teacher:
Centimeter grid paper
Completed example of monster to show students
Pencil and dark marker
Post-It Notes
Materials for the students:
Centimeter grid paper
Pencil
Construction paper of any color cut to approx. 10 x 12
Lined Paper
Additional Information/Instructions
By Author/Submitter
This lesson is aligned with Mathematical Practice Standards:
MAFS.K12.MP.1.1: Make Sense of problems and persevere in solving them.
MAFS.K12.MP.4.1 Model with Mathematics.
SOURCE AND ACCESS INFORMATION
Contributed by: Mary Kublin
Name of Author/Source: Mary Kublin
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.3.MD.3.5:
Description
Recognize area as an attribute of plane figures and understand concepts of area measurement.
a. A square with side length 1 unit, called “a unit square,” is said to have “one square unit” of area, and can be used
to measure area.
b. A plane figure which can be covered without gaps or overlaps by n unit squares is said to have an area of n square
units.
Particular alignment to:
MAFS.3.MD.3.5a:
MAFS.3.MD.3.5b:
MAFS.3.MD.4.8:
A square with side length 1 unit, called “a unit square,” is said to have “one square unit” of area, and can be used to
measure area.
A plane figure which can be covered without gaps or overlaps by n unit squares is said to have an area of n square
units.
Solve real world and mathematical problems involving perimeters of polygons, including finding the perimeter given the
side lengths, finding an unknown side length, and exhibiting rectangles with the same perimeter and different areas or
with the same area and different perimeters.
page 3 of 4 Attached Resources
Lesson Plan
Name
Wrap it Right! (Ribbon):
Description
"This lesson uses graphic models for finding perimeter and for creating formulas relating to perimeter."
page 4 of 4