It depends how she practices. If she follows a structured program it will be more than enough. I wish I played for an hour a day.

that's PLENTY time to practice, especially at first. I may go as far as to say possibly to much. I teach a few girls and boys that age guitar. The problem at that age is their attention span is not that big and so they get bored quickly. So, I challenge my students to practice for just 15-20 minutes a day. This way, their fingers will slowly build up muscle memory, they will grow strong fingers and they won't get bored and end up hating guitar because it's a chore.

I guess it depends on what she is learning and how much she enjoys it. If she is loving it and enjoys the hour of practice, then don't stop her, but don't push her for more or even for an hour.. Just my 2cents worth

I ask my students to practice for only 10 minutes a day but I stress that they must practice every single day without exception. I believe that frequent practice to be more rewarding than intensive practice. secondly I know that nearly all my students cheat and actually practice at lease twice as long everyday. One or two of my students practice for hours but only the night before their weekly lesson. I can tell because there fingers are worn out and they haven't learnt anything.

Renesongs wrote: I ask my students to practice for only 10 minutes a day but I stress that they must practice every single day without exception. I believe that frequent practice to be more rewarding than intensive practice. secondly I know that nearly all my students cheat and actually practice at lease twice as long everyday. One or two of my students practice for hours but only the night before their weekly lesson. I can tell because there fingers are worn out and they haven't learnt anything.

+1!

Curmudgeon wrote: My niece is receiving guitar lesson at school. usualy once a week. she practises at least an hour a day
Would this be enough to teach her to play????

If it's an hour of structured practice every day then that's good going. If it's 30 minutes of practice towards specific goals and 30 minutes of noodling then that's still pretty good going.

The thing is that it be organised practice, aimed at specific improvements. 60 minutes a day of repeating what you can already do would not be as beneficial.