At first I do a line test, I take a photo of each drawings with a webcam, it's faster than scanning(it's something like that animationwala.com/images/linet… ). But then when the animation is really done, I scan the drawings for better quality(but it's not the scanned version there)
You need a webcam, with something to fix it, like the link in my last com. And we use the software "Toki Line test", there is a free limited version of it, it's fine for some short animations(less than 60 frames I think). And something to fix the paper, we use a pegbar : www.gestaltung.hs-mannheim.de/… and fc03.deviantart.net/fs70/i/201… but just use anything you want, if it works, it's fine.