3D shapes and their properties

  • Platonic Planet
    problem

    Platonic Planet

    Age
    14 to 16
    Challenge level
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    Glarsynost lives on a planet whose shape is that of a perfect regular dodecahedron. Can you describe the shortest journey she can make to ensure that she will see every part of the planet?
  • Packing 3D shapes
    problem

    Packing 3D Shapes

    Age
    14 to 16
    Challenge level
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    What 3D shapes occur in nature. How efficiently can you pack these shapes together?

  • Tetra Inequalities
    problem

    Tetra Inequalities

    Age
    16 to 18
    Challenge level
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    Can you prove that in every tetrahedron there is a vertex where the three edges meeting at that vertex have lengths which could be the sides of a triangle?

  • Volume of a Pyramid and a Cone
    article

    Volume of a Pyramid and a Cone

    These formulae are often quoted, but rarely proved. In this article, we derive the formulae for the volumes of a square-based pyramid and a cone, using relatively simple mathematical concepts.
  • Mouhefanggai
    article

    Mouhefanggai

    Imagine two identical cylindrical pipes meeting at right angles and think about the shape of the space which belongs to both pipes. Early Chinese mathematicians call this shape the mouhefanggai.
  • Thinking 3D
    article

    Thinking 3D

    How can we as teachers begin to introduce 3D ideas to young children? Where do they start? How can we lay the foundations for a later enthusiasm for working in three dimensions?