COMPARISON OF POLYGON AREASAREA MEASUREMENT UNIT 2/3


Lesson preparation: For this lesson each pupil should have a small square available.

With grade 2 pupils, teachers should prepare these squares before the lesson.


Folding instructions: Fold as shown.

It is suggested that these squares should be prepared before the lesson.


Cut the squares as shown.

Prepare the smaller squares considering the number of pupils taking part in the activity.


Each pupil chooses one of his text books.

It is important that all the pupils have the same text book.


Each pupil has 2 squares. The origami sheet and the smaller cut square.


Folding instructions: Fold both squares as shown.


Folding instructions: Fold shorter sides onto each other and open the fold.


Folding instructions: On both shapes fold a vertex as shown.


Folding instructions: Turn over both shapes.


Folding instructions: On both shapes fold a vertex as shown.


Folding instructions: On both shapes fold the white triangle as shown.


Folding instructions: On both shapes fold the white triangle as shown.


Folding instructions: Partly open the white triangle. We will use these shapes as an area measurement tool.

From this stage we begin to use these tools as nonstandard area measurement tools.


We now have two different square measurement tools for measuring area.


Choose another sheet of origami paper as a third measuring area tool.


A discussion question: Which measurement unit should be used to measure the area of the binding of the text book you chose? Explain.(only use the squares as units of area measurement)


An activity: Measure the area of the binding using the the the different area units.What did you find? Explain.

While measuring it is possible that the sizes are not whole numbers. The sizes should be stated in relationship to a whole number.(approximate, smaller than, larger than)


A discussion question: Take out of your school bag an exercise book. Choose one of the area units for measuring the binding of the book and the cover of your exercise book. Compare the areas.

Pupils will learn that in order to compare areas of different shapes the same unit of area measurement should be used for both shapes.


A discussion question: After measuring the areas of the text book and the exercise book with the same unit what did you find?Explain.


A discussion question: Which has the largest area?

The concept of area comparison and a measuring unit should be fully discussed with the pupils.


A discussion question: What unit measurement of area would be used to measure the areas of these shapes? Explain.


A discussion question: What is the area of each shape?

The area number does not have to be exact.


A discussion question: Which shape has the largest area? Explain.


A pair activity: Choose two objects in the classroom and measure their areas using the same unit of area measurement. What have you found?

Discuss with the pupils the different areas of the objects. Which is larger?
 Lesson Aims
 The concept of a unit for measuring area.
 Measuring various objects with different units of measurement.
 Comparison of shape areas using a nonstandard unit.
 Name of Model
There is no special model but the units of area (squares) should be kept in a folder.
 Lesson Structure
The lesson of comparison of areas 1/3 should precede this lesson.
 Lesson Content
Understanding the concept of a unit for area measurement and comparison of area size using the same unit.
 Materials
Three origami sheets 15cm x 15 cm.