My question is, how did you learn?
How to Draw Cats by Janet Rancan. Cat fur did wonders for my pressure sensitivity.
Figure Drawing for All it's Worth and
Fun with a Pencil, both by Andrew Loomis. Some of it may be a bit out dated, like a lot of the naked women wearing high heels, but it has some very solid methods in it.
Little tutorials here, there, and yonder by artists like Sarah Ellerton, Diane Wright, and Mike Sibley. And science books and websites. All that anatomy and geology pays off.
Did you teach yourself or did you go to school?
Self taught...? Art books are a grey area to me, since it still requires accepting instruction from another person instead of blundering through it yourself strictly through observation and research.
What do you think is the best way to learn? Books, practice, classes? I know they all help, but what's the most effective way that has taught you?
Eh, depends on the person. I do very, very poorly with verbal instructions on any subject. It's all books and practice for me. If I watch a video, I mute the audio. Just can't stand the talking. XD
Some people excel with having that social interaction when they're learning, so those people need the classes and workshops more than us crabby hermits.