B.C.
I didn't like my glasses at first when I was a kid but my vision got so bad so quickly (I rapidly became very near sighted) that like it or not - if I was going to do anything the only way I wasn't going to be functionally blind was to use the glasses.
I got contacts in 8th grade (this was the 70's and it was unusual back then for a kid to use contacts that young) and wore those until I had Lasik in 1999.
As a parent of a 9 yr old - you tell her "use your glasses" when ever you see her squinting and repeat ad nauseam until she has the habit of using them without thinking about it.
She's a child - she doesn't have a choice.
Don't give her a choice when it comes to health decisions.
In 9 short years she'll be in charge of herself.
Until then - you steer.