How's teaching groups to teenagers going, then?

We’re six weeks into my experiment to teach basic group theory — the abstract theory of symmetry — to a self-selecting group of KS3 teenagers. This is a topic that is either introduced in A-level Further Maths, or else in the first year of university, so there are certainly some challenges. My curriculum plan is to do some prerequisites and examples for this first term, then formally introduce the concept of a group at the beginning of next term. From then we’ll probably more-or-less follow Pinter’s treatment in A Book Of Abstract Algebra, with a few key milestones — I’m hoping that collaboratively they will be able to classify all groups up to order 10 during the spring term. By early summer I’m hoping we can do quotient groups, including the all-important homomorphism theorem. Any remaining time can be played by ear. Some of them are cubers, so maybe we could try and describe the Rubik’s Cube group, or we could look at some other application. Or maybe we’ll all be tired by then.…