How do you find a line of symmetry?

Imagine folding the shape along a line. If the two halves match exactly, the fold is a line of symmetry. A shape can have none, one or several.

What grade is this symmetry worksheet for?

It is written for grades 2–4 and matches Common Core standard 4.G.A.3.

Is there an answer key for this symmetry worksheet?

Yes. The last page of the PDF has every answer, so you can mark the sheet in a few minutes and talk through any mistakes together.

Symmetry worksheet

Forty questions on symmetry: is the dashed line a line of symmetry, how many lines do shapes and letters have, and complete pictures on a grid.

Download the free symmetry worksheet (PDF)

Symmetry worksheet

PDF · US Letter · Grades 2–4 · 40 questions · answer key included

Download the PDF

What’s on the worksheet

40 questions on symmetry, sized for US Letter paper
2 pages of questions plus an answer key on the last page
Written for grades 2–4, matching Common Core 4.G.A.3
Name and date lines at the top, and room to show the work

Sample questions from this worksheet

Is the dashed line a line of symmetry? (picture)
How many lines of symmetry does a rectangle have?
How many lines of symmetry does the letter H have?
Shade squares so the picture is symmetrical about the red line.
True or false: every triangle has a line of symmetry.
True or false: a regular hexagon has 6 lines of symmetry.

Preview the worksheet and answer key

Practice symmetry online

Between worksheets, a few minutes of online practice keeps the skill fresh. The symmetry practice asks how many lines of symmetry a shape has, with a new shape every time. The lines of symmetry lesson has a quiz too, and transformations is the next step: reflections are symmetry on a grid.

Symmetry: a worked example (How many lines of symmetry does a rectangle have?)

Fold it top to bottom: the halves match. That is 1 line.
Fold it left to right: the halves match again. That is 2 lines.
Fold it along a diagonal: the corners don’t meet, so a diagonal is not a line of symmetry.
A rectangle that is not a square has 2 lines of symmetry.

How to use it at home and in class

At home

Keep a small mirror or a sheet of paper handy: folding is the best test. For Part D, count squares out from the red line on one side, then count the same number on the other. Letters are a fun extra: ask your child to find letters with two lines of symmetry, like H and X. The lines of symmetry lesson has more examples. Ten problems a day works better than a whole sheet at once. Mark them together with the answer key, then ask your child to explain one they got wrong: finding the mistake themselves is where the learning happens.

In class

Use the first row as a warm-up, a full page for independent practice, or five questions as an exit ticket. For a retake or a second group, make a new version with the test maker so every child gets different numbers.

Mistakes to watch for

Counting the diagonals of a rectangle as lines of symmetry.
Thinking every triangle has a line of symmetry. A scalene triangle has none.
In Part D, copying the shape instead of mirroring it, so it faces the wrong way.
Forgetting that the reflection is the same distance from the line on the other side.

What to practice before and after symmetry

Before: types of angles. If this sheet is a struggle, go back a step.
After: quadrilaterals, once this one is mostly right.
Learn it first: the symmetry lesson and the symmetry chart.