Congruent and Similar Figures

Designed by: Sally Hug, Hand Middle School

GRADE LEVEL: 8th       SUBJECT(S): Math

CORE CURRICULUM OBJECTIVE(S): Demonstrate and identify congruent and similar figures and their corresponding parts (8GE1-7)

RESTATEMENT: Students will create congruent and similar figures and their matching parts.

 OVERVIEW: Students will create their own congruent and similar figures on geo-boards, on paper and find the corresponding sides.

FOCUS/ ESSENTIAL QUESTION(S): What important facts determine whether shapes similar or congruent.

TIME FRAME: Two 45-50 minute periods - one period for kinetically creating shapes - one period for creating similar and congruent shapes with corresponding sides.

RESOURCES: 
- Gateways to Algebra and Geometry (p.186-191), for reference 
- Geo-boards 
- the boards with nails in it (enough for each student to have 2) 
- Large white paper 
- Scissors 
- Glue 
- Rulers 
- Construction paper
 - Paper/pencil 
- Rubber bands for geo-board 
- Geo-board paper (copied geo-boards)

ASSESSMENT: Students will create and show examples of similar figures using the given rubric. Students could assist in developing a new rubric.

INSTRUCTIONAL ACTIVITIES:

ACTIVITY ONE

* The teacher will provide each student with two geo-boards, several rubber bands, and the copied geo-board sheet. Students will review the facts that determine weather a shape is similar or congruent.

Similar - when polygons are the same shape but different size.

Congruent - when polygons are the same size and the same shape. 

* Following the teacher's directions the students will create similar or congruent polygons on the geo-boards. There will be one shape on each geo-board. Students should hold up both geo-boards, directed toward the teacher and the teacher will acknowledge and show different examples of correct representations. (example: Teacher says, "Show me similar triangles.") 

* Using the geo-board paper, the student will draw the shapes they have create on there geo-board...this should also be done as homework without the creating of shapes on the geo-boards. Students should create 10 similar sets of shapes and 10 congruent sets of shapes.

 * Completed activities will be displayed in classroom or hall.

ACTIVITY TWO 

* Students will create two columns on a sheet of paper; these columns should be labeled similar and not similar. The teacher will give an example of letters in the alphabet where the upper case and the lower case are similar. (C and c). The students will complete the chart using all 26 letters in the alphabet.

ACTIVITY THREE 

* Students will be place in groups of two; the teacher can designate or the students can choose partners. Students will create perfectly similar and congruent shapes on construction paper using a pencil and a ruler. Students should create 10 sets of similar shapes and 10 sets of congruent shapes (for a total of 20 sets, same as, 40 shapes) The shapes should be cut, glued and labeled on the large white paper.

Name: _________________________ Date: ____________ Period: ____

FINDING AND CREATING SIMILAR AND CONGRUENT SHAPES

GRADING RUBRIC: