Many, many moons ago now, I did all my ATPL subjects via correspondence through Trevor Thom as I was living in Tassie at the time.
Don't know if his company is still going but his lessons, notes and hand corrected problems got me through all subjects the first time.
For what its worth, I found Met to be the most difficult subject without some face to face instruction. If I recall, that subject was prepared by a met specialist not Trevor himself.