Cookie Sheet Symmetry

By Joan Moss, Beverly Caswell, Zack Hawes, Cathy Bruce and Tara Flynn

To print detailed lesson plans and materials, please click here

Curriculum Goal

Geometry and Spatial Sense

For students to describe, sort, classify, and compare two-dimensional shapes and three-dimensional figures, and describe the location and movement of objects through investigation.


Table leader can begin with short lesson (see below). Afterward, students and parents may work individually or in pairs to play “the symmetry game.”


  • Cookie sheet – with a line drawn through the centre (line of symmetry)
  • Magnetic pattern blocks
  • Construction paper and pattern block stickers (optional)

Optional Introductory Lesson

  • Show students a half of a heart drawn on a sheet of paper. Ask students what they think would happen if you cut that shape out and opened it up.
  • After gathering some ideas, cut the shape out and show them the result.

How to play individually

  • Create a symmetrical design using magnetic pattern blocks, ensuring that each piece placed on one side of the line of symmetry is symmetric to a piece on the other side.
  • Continue until a desired symmetrical design is created.

How to play in partners

  • Each player is assigned one side of the cookie sheet
  • Player 1 places a piece of pattern block on their side of the cookie sheet.
  • Player 2 places the matching piece on their side to the cookie sheet, symmetrically.
  • Players can switch turns as they wish.
  • Continue until a desired symmetrical design is created.


  1. The symmetrical designs can be made with pattern block stickers on construction paper.
  2. Please see “The Symmetry Game” in The Robertson Program Library for a complete classroom lesson on symmetry
Aroland educator and a student playing with pattern blocks