This book has always looked good to me. It has a companion volume for machine stitching. I would start with hand sewing, but if she's really intrigued by the machine, why not do some simple projects if she has the maturity to use it?
There are no classes that teach skirts and dresses? It still would help to have someone with experience teach the basic skills. It may avoid having to unlearn bad habits later. Classes are always better but after the fundamentals you might be able to get along with Craftsy or Prof. Pincushion.
These books look good:
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