A good way to do it is to have a mix.  GMP refresher training year 1-general classroom training.  Years 2&3 modular training featuring core (compulsory) modules on important general interest topics (updates to regulations, good documentation practice, what the products do, whatever the analysis of deviations tells you is a problem) and specialist modules (validation, pharmacovigilance basics, process validation)

In an effort to make GMP a little more sexy to my compounding unit, I worked with Derby Uni to create an on line GMP course that covers some basics in
•    What is GMP?
•    Basic Requirements of GMP
•    People as a source of contamination
•    Behaviour
•    Documentation
•    Equipment
•    Module Assessment

After a few drinks with friends I realised that the discussions always switch to the weird 'did you know' facts. For this reason I tried to use quirky and sometimes yucky facts to get the points across about micro like the following:

Gut  - The best estimates put the actual number of bacterial cells in the digestive system at any one time at about 100 trillion (1014 cells). The number of individual species is thought to be somewhere between 300 and 1000. The majority probably belong to about 50 species. If you could remove all of the bacteria in one person's digestive system, the whole lot would probably weigh about 1 kg (2.2 lbs).

Although it is an unsavoury discussion topic, there is a real risk to belching and passing wind in clean room environments. Bacteria from the gut escape in many ways and although these small incidents are sometimes not avoidable, we must try to prevent this in clean environments.

Saliva - Millions or micro-organisms are ejected when sneezing causing MASSIVE risk to sterility assurance. You must cover mouth to prevent projection of contamination and wash hands immediately. Even ask others to open doors for you if you have sneezed to get to wash station.

I also have an MPEG that Dr Bob P was kind enough to give me some years ago of a colony forming in high speed and they love this type of larning media.

Make GMP meaningfull and you will be able to see the results in the behaviour not just by asking the individual. Each time I enter the unit my team take great pleasure in walking in slow motion as I explained how rapid movement can expell organisms from under the garmonts. This makes me smile because I know thay understand and they can point this out to each other now with humour as apposed to not at all.

I agree with earlier comment, the skull is a little freaky Tim