YouTube is your friend. How to Crochet brings up many very good videos. How to knit has many wonderful videos. I would watch some of the videos with her and see what she might want to make. Knowing she will have something she will like when she completes the project could be the thing that keeps her interest.
I know how to crochet, learned before I was 6 from my grandmother, but can't seem to wrap my head around knitting. Now that you have brought up this question, I may go look for my knitting needles, thread and start watching some videos.