Cute book cover!! I love how it turned out!
You know talking about using scraps other than quilting -
One of my favorite activities with kids is to do a collage with clear contact paper and fabric / buttons/ etc
You cut a section of clear contact paper about 12" or so by 12" and tape it to the table so the sticky side is up
Give your child a bunch of scraps and add buttons/ embellishments that are light enough to stick on and anything else you can think of to add. I like straws / glitter / toothpicks/- Lace and ric rac would work great here and also yarn scraps.
IF they need inspiration I have cut scraps into house shapes geometrics like squares triangles etc.
You can show them simple quilt block designs or help them come up with their own quilt ideas to use here.
It's a great no sew idea for kids