How do I convert B&W penciled book drawings to illustrator colored drawings?

Question

I have an opportunity to with an author, but I want to see if I can even deliver first, if I were to take it. The author needs her current black and white drawings to be in color for a book she is putting online. The images for the children's book are scanned jpeg files of actual artwork. Her book art reminds me of stuff from the 80 or 90s - the drawings aren't Blue's Clues type of artwork. She had some already in color and showed me those. The illustrations are also created to looks to be pencil. As you can imagine some black lines are darker than others for example, lots of variety of colors in the form of lines, curves, squiggly lines to add details on the main subject (whether it is hair on a person, plants, clothes, etc).
Imagine the artwork being similar to these:http://staff.bbhcsd.org/kolism/files/2012/07/charlottes-web_1.jpghttp://literacyf1302.blog.ryerson.ca/files/2013/10/sm09.jpg
I have a few of her book illustrations and I am trying to figure it out. I've tried Image Trace (low color) but the lines become fat once you hit expand and you loose the details.
My question: 1. How do I convert this scanned image to an illustrator file with paths/points (like image trace>expand does)? 2. How do I convert black and white to color, as specific as down to the line of the pencil drawn for one detail.

Answer 1

skoofi,
Have you considered using Photoshop, keeping the resolution adequate for the final size, rescanning if needed?
If you must, the same adequate resolution would also apply to the basis for Image Tracing, and you may try to experiment with the settings.