Congruent Shapes

Daily Review:

Explain to students that we will be working on congruent shapes today. Explain how this is the same and different to similar objects. Take the first few minutes of class to discuss similar objects. Have students find objects in the class that are similar. (For example, two rectangle books in the classroom can be similar, even if they are NOT the same size.)

Statement of Objectives: (GA QCCS)

Grade: 3

Geometry & Spatial Sense; Measurement

Topic: Similarity & Congruency
Standard: Sorts geometric shapes according to same shape (similar) and according to same shape and size (congruent).

Presentation of Information:

1. Now that the class has reviewed similar objects, we will now look at congruent objects, which is a type of similar object.

2. Define “congruent”

3. We will look around the classroom for items that are congruent. For example, hold up two pieces of 8” X 11” paper. They are congruent because they are the same size.

4. Do this two or three more times, allowing students to provide input on whether the items are congruent or not.

Guided Practice:

Have students work in pairs. Each pair is to look at the following websites and answer the questions about congruent objects:

• http://www.teach-nology.com/worksheets/math/geometry/congruent/ver1/
• http://www.teach-nology.com/worksheets/math/geometry/congruent/ver2/
• http://www.teach-nology.com/worksheets/math/geometry/congruent/ver3/

Independent Practice:

1. Using Kidspiration, students will complete the activity titled, Congruent Shapes. Students will arrange and manipulate each object, matching it up to its congruent shape.

2. Upon successful completion of this activity, students will complete a worksheet from their textbook.

Formative Evaluation:

Students will have a short quiz the next day on congruent objects, in a similar format to the day’s activities. Also, after completion of the geometry unit, students will have a unit test on geometry, incorporating elements of congruent shapes.