Year 7 · Mathematics and statistics · Geometry
Triangles and angles in polygons
Classifying triangles, angle sums of triangles, quadrilaterals and polygons, exterior angles and regular polygons.
Everything for this topic in one place
- 3D lesson: Triangles and angles in polygons — Tear the corners off a 3D triangle to see why its angles make 180°, classify triangles, then split polygons into triangles to find interior and exterior angles.
- Teacher presentation — slides to put on the projector.
- Worksheets at three levels — Tūī (support), Kererū (core) and Kea (extension), each with an answer key on the last page.
- Online practice — assign it to your class in the Crateclass classroom and the results come back by themselves.
Written for Te Mātaiaho, Phase 3 (Years 7–8), with New Zealand places, money and native birds.
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More Year 7 maths topics
Powers of 10 and expanded form · Primes, factors, HCF and LCM · Integers · Rounding, estimation and order of operations · Fractions, decimals and percentages · Proportional reasoning, percentages and money · Algebraic notation and equations · Linear patterns and the coordinate plane · Perimeter, area and volume formulae · Transformations, nets and compass points · Statistical investigations, averages and graphs · Experimental and theoretical probability