Many presidents ago, where I started out as an apprentice, we had a Thursday-after-work class that was 'taught' by one of the more experienced JWs in the shop.
No attendance, no program, no requirements, no tests....
Just who wanted to show up and learn about whatever they needed to know.
One day it might be box & raceway fill. Next week, how to bend EMT. Then we spend an evening talking basics, like Ohms Law. It was very informal, and very informative. Lots of fun, and lots of sodas. I probably learned more in those 'classes' than I did anywhere else.
The boss didn't mind us being there after hours as long as two things happened: We were serious about learning the trade, and stuck to the topic, and we made sure the shop was locked up when we left.