SymmetryUnit of Study 11: Plane Shapes in MotionGlobal Concept Guide: 3 of 3

Content Development Misconception Alert – A common misconception that students

have is only seeing a vertical line of symmetry when a shape has multiple lines of symmetry (horizontal, diagonal).

Misconception Alert - Another misconception is that if a shape has congruent parts, it must have symmetry. This is not true.

A shape is only symmetrical if when folded it creates a mirror image (matches perfectly).

Day 1 Use the Unlock the Problem p. 443 along with the Connect to

Science p. 446 to have students derive a definition of symmetry and line of symmetry. They can use the examples and non-examples.

The Illuminations link on the GCG is a valuable resource when introducing symmetry.

Look for examples and non-examples of symmetry around the classroom.

Geo Reflectors allow students to physically see symmetry and lines of symmetry.

Day 2 Utilize CPALMS: Symmetry in Your World Activity linked in the

GCG to teach using real world symmetry examples. This document contains a variety of different activities and lesson ideas.

If using Go Math for this concept combine lessons 10.8 and 10.9 for this day. Omit lesson 10.10, it can be used as an extension or enrichment.

The Unlock the Problem on TE p. 447 can be used as an engage activity, when finding more than one line of symmetry. A Post-It Note works well for this activity.

Enrich/Reteach/Intervention Reteach – Use die cut or outlines of shapes and have students

fold the paper in half to identify lines of symmetry. Students can also use Mega Math activity referenced in the GCG under the Interactive Online Resources.

Enrich – Have students create shapes with specific lines of symmetry. Create a shape with exactly 0 lines of symmetry. Create a shape with exactly 1 line of symmetry. Create a shape with exactly 2 lines of symmetry. Create a shape with exactly 3 lines of symmetry. Create a shape with exactly 4 lines of symmetry.