I'm very nearsighted and read quite a bit about ortho-K, but never did it. My optometrist said it was fine, but didn't highly recommend it.
I just got regular soft contacts when I was in HS, and was more than happy with those! Now, they have some fantastic disposable contacts in various prescriptions, so maybe just do that for your DD?
My optometrist said that ortho-K doesn't really actually correct the nearsightedness, just flattens the cornea temporarily, and then the cornea goes back to it's normal shape. From what I understand, if you're nearsighted, your eyeball is longer than normal, and you can't really change that!