Wow these kids did great! I'm trying to remember what my first project was because I started sewing about that time with my Grandmother. I think it was strips because she said I had to learn the "feel" of the machine.
If you make a couple of squares you might try putting 2 sides together, hand baste it with long stitches then say this is where you sew with your machine. Tell her or write " Just stitch with your machine over my stitches". You could do that with several of the blocks till she gets the hang of it.
Probaby speed (was with my daughter) from pushing the floor pedal too hard could be an issue.You might try sending her long strips first, then squares. Just so she can get the feel of the sewing machine and see her progress.
If it were me I'd send her little things to practice on every week before sending a complete kit. Kinda like a correspondence class. I bet she loves to get mail. Who knows maybe your daughter will even get interested??? Good luck!