Patterns for
regular solids
Aunt Annie's Crafts
Geometric Solids
What you will make -
In this project make three of the five Platonic solids—tetrahedron, octahedron, and icosahedron. The tetrahedron is easy to make, while the icosahedron can be hard for children under ten. Make the tetrahedron first before trying to make either of the other two solids.
These geometric models can be used for things beyond learning about solid geometry. Decorate them and make a colorful mobile with a paper plate and some string. Use them as Christmas tree decorations, or use one as a giftbox and put a small gift inside.
Geometric solids are three dimensional objects like spheres, cones, and cubes. Solids with only flat surfaces and straight lines are known as polyhedra. There are many different polyhedra, but five of them have the property of being regular. A solid is regular if all faces are the same and the same number of planes (faces) meet at each corner (vertex). Five solids qualify as regular (also called Platonic)—three based on triangles (tetrahedron, octahedron, and icosahedron), one based on squares (cube), and one based on regular pentagons (dodecahedron).
The solids in this project are all based on equilateral triangles. The tetrahedron has four sides (or faces), while the octahedron has eight and the icosahedron has twenty. The tetrahedron has three triangles that meet at each corner (or vertex). Four triangles meet at each corner of an octahedron, and five triangles meet at each corner of an icosahedron. Examine your models to see these properties.
Here's what you need -
- Card stock, plain or colored
- Glue or double-sided tape
- Scissors
- Bone folder or empty ballpoint pen
- Ruler
This project is rated EASY to AVERAGE to do.
How To Make Geometric Solids
Read all of the steps before starting.
- Step 1: Choose a pattern and print it
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Choose the geometric solid to make—there are templates for a tetrahedron, an octahedron and an icosahedron. Download and print the pattern.
Choose a design that prints in color or select a black&white pattern to print on colored cardstock or use your creativity to decorate the solid.Patterns are Adobe PDF files. The Adobe Reader is available for free.
All of Aunt Annie's project patterns are designed to be printed on standard letter size paper (8.5"x11" or A4). When printing from Adobe Reader you may need to select Auto-Rotate and Center or Choose paper source by PDF page size to ensure the best fit.
- Step 2: Color Pattern (optional)
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Color the pattern template as you like with markers, colored pencils or crayons. You don't need to color the glue tabs.
- Step 3: Cut
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Cut around the polyhedron's pattern on the outline. Try to make your cuts very straight and smooth. There will be one piece, ready to fold, after you cut. (The octahedron pattern and tetrahedron pattern have two templates—small and large.)
- Step 4: Score
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Scoring the fold lines makes for easier folding and sharper creases. The fold lines are marked in blue on the illustration.
To score: Turn the template with the printed / decorated side up. Use a ruler and the empty ballpoint pen (or bone folder) to make an indent along the fold lines.
- Step 5: Fold
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With the printed side down, fold each line that has been scored.
Be sure all folds are sharp.
- Step 6: Glue
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Gently form the solid into shape, referring to the illustration on the pattern. Carefully glue each tab into place. The tabs can be glued on the outside where the sides meet or on the inside. It is much easier to glue the tabs on the outside, but the solid will look neater with the tabs glues on the inside.
Before you start -
- Make a place to work.
- Read all the directions.
- Get everything you need to do the project.
- Think about the project. Imagine how it will look and what you will do with it.
Are you ready?
Okay, get started!!!
Tip: Glue tabs can be glued inside for a neat look.
Tip: This tetrahedron has the glue tabs glued on the outside for a different look. This is a much easier way to glue the solid models.
Project Extra: For a cute set of solids or a giftbox, print these Polka Dot ePapers on cardstock with the solid's pattern on the reverse side.
The polka ePapers were printed on pastel cardstock to make these giftboxes. Holes were punched and laced with ribbon then the gift boxes were tied closed.
Tip: The octahedron pattern includes two sizes. (So does the tetrahedron pattern.)
Tip: The icosahedron colored model has five colors that meet at each vertex.