Main task: build the five platonic solids and discover some properties by filling the table:

Find Euler's formula:

#edges +  ?  =  #sides + #corners

Higher order tasks (HOTs)
1. Find out which solids can fill space.
2. Find out how a tetrahedron can fit completely inside a cube and make a sketch of it.

• cube and tetrahedon (tetra fits into cube)
• octahedron (matches sides of tetrahedron)
• dodecahedron
• icosahedron

Additional remarks from classroom experience:
Folding will be neater if the lines are grooved with a scissor side along a ruler.
Classroom discipline can be established by students taking turns in assembling all scraps.

Assessment criteria:
- quality of solids (neat work)
- correct formula
- wording on how the formula was found

What can be learnt:

• terminology of mathematical objects
• spatial skills
• making tables
• finding rules

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