I have bought books before on "how to draw children" or "drawing people", but they always bored me- seemed better suited for the fine artist because every person in there was so stiff and posed. About a month ago I began reading Drawn to Life volumes I and II, which are collections of amazing notes that Walt Stanchfield gave to his animation students over the several years he was with the Walt Disney company. These books are all about giving life to your subject- movement, action, gesture... anything but stiff and posed. He talks a lot about capturing the essence of that person, a maximum amount of gesture with a minimum amount of lines. It also talks about feeling that gesture that you are drawing and understanding why your subject is feeling that way. Even though these notes were intended for animators, they work wonderfully for me because as a children's book illustrator my subjects (the actors in my story) need to appear to be in movement, full of life, and even the quietest of gestures needs to be relatable to the child reading the book.
Read the rest (and thanks to Liz Mills for the link).