TEACHERS:
Jenene Woodruff
Adapted from HandsOn Standards (Common Core)

SUBJECT:
Explore the meaning of symmetry

STANDARD:

4.G.3 Recognize a line of symmetry for a twodimensional figure as a line across the figure such that the figure can be folded along the line into matching parts. Identify linesymmetric figures and draw lines of symmetry.

OBJECTIVE (EXPLICIT):

I can identify lines of symmetry and make symmetrical figures.

EVIDENCE OF MASTERY (MEASURABLE):
Recording sheet from group work, created symmetry mask, possible formative assessment problem provided, independent worksheet available at the end.


KEY VOCABULARY:
Symmetry, symmetrical

MATERIALS:

Pattern Blocks (50 assorted for each pair)

Crayons (10 per pair)

Paper (4 sheet per pair)

Pencils (1 per student)

Construction Paper (1 per student)

ENGAGE (MAKE CONTENT AND LEARNING RELEVANT TO REAL LIFE AND CONNECT TO STUDENT INTEREST)
“Have you guys ever watched Sesame Street? Have you ever seen that game, “One of these things is not like the others?” (I sing this) “Well, we’re going to play that game…”

BEFORE

TEACHER WILL:

Draw 45 pictures/shapes on the board, all but one should be symmetrical.

Tell the students that all of the shapes show symmetry but one.

Have them share with their partner what makes a picture/shape symmetrical.

Have each pair of students gather the supplies for the activity.

STUDENT WILL:

Examine the pictures/shapes for common traits.

Share with a partner what is meant by symmetry/symmetrical.

EXPLORATION PROBLEM ABOUT SYMMETRY:

Alexander wants to make a face mask of his favorite action hero to wear on the night of his class costume party. The mask he wore last year was torn in half, but Andrew is hoping to use it as a pattern. How can Alexander create a whole face mask from the half he has?

DURING

TEACHER WILL:

Read the problem with the students.

Tell pairs they will use the paper and pattern blocks to create the “fixed” version of Alex’s mask.

Monitor students for misconceptions of what symmetry is, and complete intervention with those pairs that are having difficulties with symmetry. Review board examples with them.

Possible formative assessment, have students try the following problem:
Which shows a line of symmetry?
A. B. C. D.

Allow students to create their own symmetry masks by using the pattern blocks for tracing on construction paper. They can then cut out or color the symmetric patterns to create their mask.

STUDENT WILL:

Use pattern blocks to create a visual representation of symmetry by “fixing” the torn mask, and draw the representation on paper.

Design and create a Symmetry Mask to display.

COTEACHING STRATEGY IF APPLICABLE

AFTER

TEACHER WILL:

Have students share their designs of their masks, explain to the group why the patterns are symmetrical.

STUDENT WILL:

Share work with the group and communicate their knowledge of symmetry as it pertains to the masks.

Display the Symmetry Masks on the class math board.

COTEACHING STRATEGY IF APPLICABLE
