22ORIGAMI:  LESSON PLAN 1

Name: Baburam Kharel (BK)

Title of lesson: Surface Area

Date of lesson:

Length of lesson: 100 minutes

Description of the class:

                          Name of course: Geometry

                          Grade level: 9th and 10th                                                                         Honors or regular: Pre-AP

Source of the lesson:

               Original

TEKS addressed:

      Geometry (e).1(D) Students find surface areas and volumes of prisms,                                                               pyramids, spheres, cones, and cylinders in problem situations.

I.             Overview

Making their own objects (origami) will raise studentsÕ sense of ownership in their learning process and enhance their creativity. To have a class with origami skills will be tremendously helpful in teaching geometry throughout the year. Finding dimensions without using a ruler will encourage them to think and use their prior knowledge, for example Pythagorean Theorem, rather than following a recipe. Consequently they will have a clear concept of what surface area is.

II.   Performance or learner outcomes:

Students will be able to:

á        Create two kinds of origami boxes:  open-top and closed one.

á        Find the dimensions of the boxes without using a ruler where the size of the paper is known.

á        Find/calculate the surface area of rectangular prisms.

á        Relate the surfaces areas of the boxes to the area of the paper used.

á         Write the units of area correctly.

III. Resources, materials and supplies needed

 Origami/patty papers.

IV. Supplementary materials, handouts.

                 Hand outs showing the pictures on how to make origami boxes.

Five-E Organization

Teacher Does                      Probing Questions                                     Student Does      

Engage:

Asks some warm up questions related with surface areas.

Bring up a story that I always buy some fabric for my suit when I go to other countries for vacation because they are cheaper there.  You might actually tell them how much you pay for a suit you have made in another country (including the cost of the fabric) and compare it to how much a suit would cost you if you bought it in the US.

What is surface area?

Example?

Units?

   How is the general shape of a fabric you buy from a store?

 How does a tailor or a fabric sales person figure out how much fabric you need for certain clothing, say a shirt?  Look on the back of a pattern too.

What do you mean by the body size?

So in short, what is the tailor trying to find out in your body before he tells you how much fabric you need?

Rectangular, Square!

Body size!

Height, size of waist, length/size of armsÉ

Some may say weight!

Surface area.

(Some may say volume)

Area of the faces.

Boxes, room, etc.

Explore:

Pass the hand outs and origami papers to each student.  They can work individually or in groups of two or three but everybody is responsible individually.

Guide their activities with constant supervision.

      You are given two pieces of papers with known dimensions:  Following the steps in the hand out where is the handout youÕll have them follow?  You didnÕt attach it, use one of the papers to create a rectangular prism (box) with open top and the other one to create a box with all faces closed.  Find out the dimensions of the boxes without using a ruler. You can unfold the boxes if you need to. Calculate the surface areas of both the boxes and note those down with proper units. Now find out in each case what percentage of the paper is counted (used) in the surface areas.

Work individually. Ask the teacher or their friends for help.

Explain: 

Act as a discussion leader, confirms their results and helps understand the concept of surface area and efficiency.

What are the dimensions of the boxes? How did you find those?

What are the two surface areas? Units?

What are the two percentages?

Why are the two percentages not the same?

Which case is more efficient? Why?

Why none of the values are hundred percent?

Different students are expected to use different techniques of finding dimensions. Smart ideas will have to be shared.

[ paper 8.5 * 8.5; open box: 3 * 3 * 1.5; closed box: 2.2 * 2.2 * 2.2]

Paper: 72.25 sq inches, open box: 27 sq inches, closed box: 29.04 sq inches.

37.37% and 40.19%.

Because one is open top and the other one is closed.

The closed box (40.19%). Utilizes more paper.

Because some folds of paper are not counted/used in surface areas.

Extend / Elaborate:

Would those percentages have changed if you had used cm instead of inches and vice versa?  This is a good question.  Students might not give you a correct response though, so be prepared to work it out or have them work it out to ÒproveÓ it.

How can you now find the percentage of paper not counted towards the surface area because of the folding?

Does a tailor waste that much of your fabric?

Does he then use 100% of the piece of fabric?

No. The ratio will not be affected.

Subtract from 100.

No, he is allowed to cut and sew/join.

No but Étries to be close.

  Evaluate:

Wrap up:

Invite a volunteer to explain what they learned from the activity. Teacher will add to that if needed.

All of you turn in your works sheets for grading.

Also collect and save those origami boxes in the plastic bin for the next class activity.