Symmetry as a transformation + coding

Grades 2/3 Teacher InterviewSide-By-Side

Interview with Bronna Silver, Grades 2/3 teacher, St. Andrews PS, TDSB


See the coding environments, lesson plans, stories, and other resources for this lesson at

Use the tab above to see the Symmetry Side-By-Side.

Discuss this on TVO’s TeachOntario [coming soon].

1. We can see symmetry as a transformation: a transformation that leaves a shape unchanged. And we can see it as a permutation.

2. We made connections to angle measurement, to fractions, to organized lists, & to probability.

3. I was surprised how students responded, and how they engaged.

4. In a coding environment, students have an opportunity to show what they can do.

5. Introducing new ideas about symmetry in a story setting helped make learning more meaningful and memorable.

6. Students shared their learning at home, and parents sent feedback and comments to the teacher.

7. Symmetry + Coding song written and performed by grade 2/3 class.

8. Bumper symmetries: defining the rotation symmetries of the square.

9. What might happen when the 4 rotation symmetries bump onto one another?

10. Demo with code and student predictions.

11. Students work in groups to model the problem.

12. Students work with code.


Below is a lesson sequence on Symmetry using 2 different pedagogical approaches, shown side-by-side:

  • the pedagogical approach on the left is fairly typical
  • the pedagogical approach on the right offers a mathematical surprise

The intent is not to pick one approach over another, but to see that both approaches are of some value.

Try these ideas in your classroom.

How do students react differently to each pedagogical approach?

We’d love to hear your feedback. Please send comments to George Gadanidis at