SYMMETRY ALL AROUND US

Objective:

Given a shape, the student will determine if it has reflective symmetry and indicate any lines of reflection.
The students will recognize that our world is filled with symmetry.

scissors
paper
colored markers
Symmetry All Around Us Activity Sheet

• Have students cut out a random triangle .
• Ask them to fold it exactly in half.
• Discuss the types of triangles that will fold in half, contrasting them with the types of triangles that will not.

DO NOT apply your marker directly to the screen. We suggest printing a hardcopy of the activity sheet directly from your browser to work on.

• Have students work through the activity sheet slowly and carefully using colored markers to highlight the lines of reflection.
• The term line of reflection is used in favor of synonymous terms like line of symmetry or mirror line.
• Figures 1-4 introduce reflective symmetry and the idea of a smaller shape repeating to form a larger, more interesting pattern.
• Figure 5 shows how diagonal symmetry can be used to distract your vision to the side, making the object appear shorter or crooked.
• Figures 6-7 introduce the concepts of global (symmetry to others) and local (symmetry to self) symmetry.
• Figures 7-8 show how reflective and rotational symmetry can exist together and give a design a special appearance.
• Figures 9-10 revisit rotational symmetry by examining shapes with so much reflective symmetry that they become circular.

• Discuss how the symmetry of the basic repeated shape may be different than the symmetry of the pattern.
• Emphasize the connections between the basic repeated shape and the larger symmetric patterns.

• Have the students take pictures of cool symmetric stuff or make a video with a symmetric theme and a funky symmetric soundtrack.
• Pursue the concept of symmetries inside of other symmetries.
• Explore asymmetry and how that relates to nature.
• Write a paragraph explaining how symmetry influences the way buildings appear, cars move, games are played, etc.