S.D.
my 10 year old rides a 20 inch. I think when she becomes more conf. I will move her up too at 24 inch. They have to be able to touch the ground well to save themselves I would think and the handle bars are much wider as they may hunch over more then they should. So I was not ready to do the bigger bike. I think you can raise the seat and stuff up to help her grow into it for at least a year or two. Just depends how tall she is.