[jacquesm]

Not all teachers are equal. There are plenty of places where the current state of chemistry education is still teaching kids the electrons go around the nuclei in perfect little circular orbits and that electrons that are 'shared' do so by making figure 8's.

[Symbiote]

In England and Wales, the circular orbits simplification is used at GCSE [1] (age 15-16), but the orbitals/probability thing at A-level [2] (age 16-18).

My teacher (the same for all four years) explained that the first model was an oversimplification, but I don't think it's inappropriate to use it.

[1] http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr_pr...

[2] http://www.s-cool.co.uk/a-level/chemistry/atomic-structure/r...