We get together one lunchtime a week to bounce (or might we say, carom?)
a few maths ideas off some like-minded people.

The aim is to look at some sweet mathematics
discovered 'off the beaten track' of the syllabus (hence the word 'offbeat').
If only time allowed us to study this in formal lessons...

We meet for maybe 40 minutes. We prepare by trying some maths generated by the Carom activity chosen.
Half of the forty minutes goes in us actually doing some maths (vital), and the other half in learning from the Powerpoint.

This is maths that provides a useful bridge into undergraduate mathematics too;
Carom members are never short of things to talk about at interviews.

or