# Teaching 4.G.A.3 – Recognize and Draw Lines of Symmetry & Identify Line-Symmetric Figures

## Geometry – 4th Grade

**Draw and identify lines and angles, and classify shapes by properties of their lines and angles.**

Recognize a line of symmetry for a two-dimensional figure as a line across the figure such that the figure can be folded along the line into matching parts. Identify line-symmetric figures and draw lines of symmetry.

**Teacher Notes**

A line of symmetry divides a shape into two congruent parts. A figure can have one line of symmetry, more than one line of symmetry or none at all.

**Student Knowledge Goals**

I know a figure is symmetric when it can be divided by at least one line into two congruent parts where the two parts are mirror images of one another.

I know a line of symmetry is a line on which a figure can be folded so the two parts match exactly.

I know a figure can have more than one line of symmetry.

I know a figure with at least one line of symmetry is symmetric.

I can identify shapes that are symmetric.

I can categorize two-dimensional figures as line-symmetric and non-line-symmetric.

I can draw in the line(s) of symmetry for line-symmetric shapes.

I can explain why a given shape is non-line-symmetric.

**Vocabulary**

line of symmetry

symmetry

**Lessons**

Engage NY Module 4 D-12 – Recognize lines of symmetry for given two-dimensional figures; identify line-symmetric figures and draw lines of symmetry.

Engage NY Module 4 D-14 – Define and construct triangles from given criteria. Explore symmetry in triangles. **Related but not CCSS required*

Symmetry

Lines of Symmetry

**Student Video Lessons**

Learn Zillion – Recognize and draw lines of symmetry and line-symmetric figures

Study Jams – Line of Symmetry

**Online Problems and Assessments**

Khan Academy – Questions and Video Lessons

Lines of symmetry

**Online Games**

Symmetry

**Printables**

Symmetry

Assessment Task 1

Assessment Task 2

Assessment Task 3

Assessment Task 4

Assessment Task 5

Assessment Task 6