Why are there no squares on the Sydney Harbour Bridge?

If you look closely at our famous “Coathanger,” you’ll see thousands of triangles, but not a single empty square. Do you know why?

Today’s final Real World Application lesson from Level D is all about Rigid Geometry. We’re exploring why triangles are the “superheroes” of engineering and how they keep the world’s heaviest structures from collapsing.

It’s a hands on lesson that will have your kids looking at every bridge, crane and roof-truss in a completely new way!

Like all the rest this week, it’s free to download right here.

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Milestone Maths is a home-grown, print-based Australian homeschool maths curriculum written by an Australian homeschooler, specifically for the Australian homeschool community. Our mission is to make maths simple, relevant, and engaging for Australian homeschool families.