Lesson 1

Explore Perimeter and Area of Composite Shapes

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Students will be able to explore the differences between area and perimeter using models

Big Idea

Students further their understanding of area and perimeter by first considering a design for a bumper car ride.


1 minutes

Teacher introduces the lesson starter (hook)  followed by objective.  Teacher shows the exit ticket problems to explain criteria for success.  Students follow lesson presentation and write in guided notes when expected to. (8-10 minutes)

I will hold up an inch square (color tile)  and a ruler or measuring tape.  I’ll ask:  “What do these objects have in common? What is different?”  I’ll accept a wide variety of answers but will stress precise languarge as students give examples (MP6).  The point is for students to understand that these 2 tools are used to measure different attributes of an object.  (MP5).  It also serves as a pre-assessment of how what students know/remember about area and perimeter.

The floor tiles and rails of a bumper car attraction are used as a metaphor for area and perimeter respectively.  The questions on the first two examples are meant to help students make this connection:  rails à perimeter and floor tilesàarea.

Guided Practice + Independent Problem Solving

25 minutes

Students work with their neighbors to find the area and perimeter of a possible bumper car floor.  Both shapes have the same area but a different perimeter.  The point is for students to see that shapes with the same area do not necessarily have the same perimeter.  Then students are asked to create a shape with the same perimemter but different area.  This can be a challenge.  The color tiles allow students to explore and sucessfully problem-solve (MP1) without feeling pressure to get the right answer immediately.  I will break this section into two parts.  I want to make sure students have sucessfuly completed GP1-GP4 before moving on.  When we discuss solutions to GP5, I will display various student solutions on the SmartBoard using the document camera.  I will ask students to discuss with their partners whether or not each shape meets the criteria.  The discussion of this problem and GP6 provide a good opportunity for students to practice presented evidence (MP3) at a basic level.  

Next students work independently on a similar set of problems.  Before they begin, I will point on question #6, so that students are ready for a brief discussion.  This question will be used to help summarize what we know about area and perime

Lesson Summary + Homework

10 minutes

We will quickly discuss solutions to the independent problem solving.  Again, question #6 is meant to solidify a student’s understanding of the difference between area and perimeter.  Students will then take the exit