I do German cont. at Open High School.
It's definately not my preferred method of learning, but since I like the subject a lot, that keeps me motivated.
PROS
- get to hang out in the air conditioned room off the library with computers
- can treat it like a free if you're ahead or will do the work at home
- can do it on any line
- it's fun when you go to sydney and meet your class.
- the course is very structed... not like having a teacher who never shows up or goes off on a tangent easily
CONS
- lack of teacher/class interaction
- i don't entirely feel comfortable talking to my teacher on the phone
- can be hard to stay motivated
- don't get much speaking practise - not good in languages!
What subject were you thinking of?