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The instructor tells children the following:

  • Thus far, you've created flat drawings in the two dimensions of length and breadth.
  • Now we will study prisms - form in three dimensions - length, breadth, and depth.
  • We will draw three dimensional (3D) representations of the triangle, the rectangle, and the circle.

The instructor shows children the following in the top image:

  • Rectangle
  • Right Triangle
  • Equilateral Triangle
  • Obtuse Triangle
  • Rectangular Prism
  • Right Triangular Prism
  • Equilateral Triangular Prism
  • Obtuse Triangular Prism
  • Three Dimensional House (Combination of Triangular and Rectangular Prism)

The instructor shows a a real example of a rectangular prism:

  • Use a crayon box or other small box as a model.
  • Place the box on the table before you in the position of the bottom image.
  • Observe that the box has:
  • Six faces. Top face, bottom face, front face, back face, right face, and left face.
  • Four vertical edges, four horizontal edges, and four horizontal receding edges:
  • Twelve edges or lines in all - three sets of four lines each (four vertical, four horizontal, four horizontal receding).
  • The four receding lines all converge on a point on the horizon.

The instructor helps children master drawing a rectangular prism:

  1. Use an erasable pencil for the drawings. Draw freehand without a ruler.
  2. Draw the front face - A, B, C, D.
  3. Draw a line above the front face of the rectangle representing the horizon.
  4. Choose the eye point of vision on the horizon and mark it with a dot.
  5. Draw light lines from each of the corners to the eye point.
  6. Draw the back face E.
  7. Finish the visible lines with heavier strokes.
  8. Add a few trees - recall that the horizon passes through where the branches/foliage meet the trunk.
  9. Repeat steps above until mastered.

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