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Habits of Mind - Polyhedra

• Thinking flexibly
• Thinking interdependently
• Persisting

Target audience:
Home groups – Groups of 2 or 3

Resources:

30 satay sticks & 12 rubber bands per group


Activity:

1. Introduce the Habits of Mind:
• Thinking flexibly
• Thinking interdependently
• Persisting

2. Explain the concept of “polyhedra” (plural) and “polyhedron” (singular):
- A polyhedral is a three-dimensional shape with various numbers of polygonal faces
joined together at edges. The most common polyhedral use “regular polygons” that
have sides of equal length and angles between adjacent sides that are all the same. The
most common regular polygons are the equilateral triangle and the square. A
polyhedron comprised from regular polygons is called a regular polyhedron.
- The most easily recognised polyhedron is the cube: 6 square faces, 12 edges, 8 vertices.
- There are three regular polyhedra based on the equilateral triangle:

o Tetrahedron: 3 faces, 6 edges, 4 vertices (3 faces meeting at each vertex)
o Octahedron: 8 faces, 12 edges, 6 vertices (4 faces meeting at each vertex)
o Icosahedron: 20 faces, 30 edges, 12 vertices (5 faces meeting at each vertex)










TETRAHEDRON OCTAHEDRON ICOSAHEDRON




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