Why do this
offers opportunities for children to visualise a
3D shape. It also encourages conjectures and justifications.
To begin with, encourage children to make conjectures about
the number of different tetrahedra, asking pairs of children to
come up with justifications for their ideas.
Having polydron available for children to make tetrahedra
would be helpful. Alternatively, stickers could be stuck on
ready-made tetrahedra. Children might also want to draw nets so
isometric dotty paper would be useful.
Where could the other
Can you find another way?
How do you know the tetrahedra are different?
How will you record your tetrahedra?