Fourth graders learn that a line of symmetry folds a figure into two matching halves, test figures for that fold, and sort shapes and letters into symmetrical and not symmetrical.
Students will be able to…
Fold a paper heart and the halves match; fold the letter R and they do not. What makes a figure symmetrical, and how do we find its lines of symmetry?
Project this and sort each figure into symmetrical or not — tap a figure, then tap whether it has a line of symmetry.
Tap any phase to open the teacher moves and student actions.
Fold a paper heart down the middle and the two halves match exactly. Fold the letter R and they do not. What makes the difference?
Students sort figures as symmetrical or not.
Students draw lines of symmetry.
Students make a symmetric design.
Students reflect on symmetry.
Aligned to the Common Core State Standards for Mathematics (Grade 4).
Recognize a line of symmetry for a figure and identify line-symmetric figures and draw lines of symmetry.
Classify two-dimensional figures based on the presence or absence of lines of a specified type.
Draw points, lines, line segments, rays, and angles, and identify them in figures.
Look for and make use of structure.
Preview the three formative checks. Tap “Sample answer” to see what mastery looks like — hide them before you print for students.
Have students draw a line down the page, draw a shape on one side, and mirror it exactly on the other, so symmetry becomes something they make. A printable lines-of-symmetry worksheet is in the Mathematics library.
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A print-and-go review sheet with a built-in answer key. Tap “Show answer key” to reveal answers, or print the clean version for students.