Greedy Triangle Research Paper

Lesson Overview: Using the book, The Greedy Triangle, by Marilyn Burns, students will learn to identify and sort two-dimensional and three-dimensional objects.
Sources/References: Burns, M. (1994). The Greedy Triangle. New York, NY: Scholastic.
Cranston, L. (n.d.). Going on a Shape Hunt: Integrating Math and Literacy. Retrieved March 09, 2016, from http://www.readwritethink.org/classroom-resources/lesson-plans/going-shape-hunt-integrating-776.html?tab=1#tabs
Sherman, L. (2008). Teaching The Greedy Triangle: A Lesson with First and Second Graders. Retrieved March 9, 2016, from http://www.mathsolutions.com/documents/9780590489911_l.pdf

NCTM: Geometry
Indiana Math Standard:
1.G.1 Identify objects as two-dimensional or three-dimensional. Classify

and sort two-dimensional and three-dimensional objects by shape, size, roundness, and other attributes. Describe how two-dimensional shapes make up the faces of three-dimensional objects.
1.W.6.2c Spelling unknown words phonetically, drawing upon phonemic awareness and spelling conventions.

Objective(s)
At the end of the lesson, students will be able to identify two-dimensional and three-dimensional objects with 75% accuracy. Assessment Tool with Assessment attached
Students will be assessed using the shape sort activity sheet and the shape walk investigation activity sheet. Mastery or Performance Level, Criteria
Students will participate in a shape walk investigation where they will identify real life examples of two-dimensional and three-dimensional shapes using the shape walk investigation activity sheet. Passing criteria will be 3 out of 4. For those students who do not achieve this criterion, we will review both two and three-dimensional shapes with these students in small groups to insure understanding.
Instructional

Plan

Materials/Equipment

For the Student:
• 1 geo board
• Rubber bands
• 1 shape sort activity sheet
• 1 shape walk investigation activity sheet
• 1 pencil
• Assorted crayons
• 1 shape bucket (per four students)

For the Teacher:
• The Greedy Triangle, by Marilyn Burns
• The Greedy Triangle PowerPoint
• The Greedy Triangle accordion prop
• SMART Board
• Set of student materials to model the activity
• Overhead projector

Teacher Prep Materials & Instructions:
The Greedy Triangle accordion prop:
• 1 10 ½” by 8” piece of thick cardboard
• 7 fasteners
• Ruler
• Pencil
• Hole punch
• Scissors

1.

Measure and cut your cardboard into eight 6” x 1” strips.
2. Using your hole punch, punch one hole approximately 1” from the end of your strips on all eight strips.
3. Punch another hole approximately 1” on the other end of the strip. But do this for only six of your strips.
4. Take one of the strips that has only one hole punched at the end and connect it end to end with a strip that has two holes punched using one of your fasteners.
5. Now take another strip that has two holes punched and connect one of hole punched ends to the other end of the piece that you connected to your base.
6. Continue to string the strips together end to end with the fasteners.
7. Once all of the pieces are connected your piece will fold like an accordion and open up when you pull on each individual strip.

Shape Bucket: (1 bucket for every four students.)
• 1 6 qt. bucket
• 1 piece of poster board
• 1 Marker
• 1 wooden block
• 1 toilet paper or paper towel roll
• 1 foam craft cone
• 1 post it note
• 1 paper ruler
• 1 empty Tolberone box
• 1 Christmas ball

ornament
• 1 playing card
• 1 play dollar bill
• 1 orange

1. Fill the bucket with the last ten of the items listed above.
2. Divide the poster board in half, creating two categories.
3. Label the categories as “2-D” and “3-D.”

Academic Vocabulary, as applicable:
Three-Dimensional: An object that has height, width and depth. Examples of three-dimensional objects are an ice-cream cone is a cone and a soup can is a cylinder. Can also be represented as "3D".
Two-Dimensional: A shape that only has two dimensions such as width and height and no thickness. Examples of two-dimensional objects are circles, squares, and rectangles. Can also be represented as "2D".
Retrieved from http://www.mathsisfun.com/definitions/three-dimensional.html and http://www.mathsisfun.com/definitions/two-dimensional.html on March 9, 2016.
Instructional Procedures
Day One:
Lesson Introduction:
1. Call the students to the carpet in front of the Smart Board.
2. Do a Think, Pair, and Share with your students.
3. Ask students the question “What makes a shape different from another shape?” “For example, what makes a triangle different from a square?”
4. Draw a triangle and a square on the Smart Board.
5. Give the students thirty seconds to think about it silently.
6. Instruct students to turn to a neighbor and share their thoughts about what makes a shape, a shape.
7. Invite two or three students to share their thoughts with the class.
8. Tell the students that we are going to be reading a story about a greedy triangle.
9. One teacher will read The Greedy Triangle, by Marilyn Burns, while the second teacher is displaying the Greedy Triangle PowerPoint and operating The Greedy Triangle accordion prop.
10. Use the accordion prop as soon as the book begins by turning it into a triangle.
11. When the greedy triangle turns into a square, pull up another strip of your The Greedy Triangle accordion prop to transform your triangle into a square.
12. Repeat the step of pulling up another strip every time the greedy triangle changes shape (until you reach an octagon.)
13. After you finish reading the book, ask the students to recall what kind of things the greedy triangle could be when he transformed his shape.
14. Call on students who have their hands raised to give you answers, and draw those shapes on the Smart Board.
15. Ask students to identify shapes that are similar and why they are similar (i.e. they are both triangles or they both have three sides.)
16. Tell students one way that we can identify shapes is by the number of their sides.
17. Show and discuss with students slides 23-28 on The Greedy Triangle PowerPoint, which are about different polygons (triangle-octagon.)
18. Inform students to return to their seats.