I don't have any magic solutions for your - I am a middle school teacher and if I could find a fix it for children who don't do homework, I'd be rich!
I have tried everything - including CALLING children at home everyday with their assignments, emailing daily with parents, packing backpacks, faxing assignments, emailing assignments, having parents drop off late assignments at my home, the day before report cards, so I could mark it in time to count it towards their grades - you name it, I've done it.
Does any of this work??? Maybe in the short term - but not long term because the kids aren't making any changes - it's like taking those diet shakes - yes you lose weight when you are drinking them, but as soon as you stop taking them, and go back to eating the way you did before, you gain all the weight back, kwim? They aren't making any changes to their behaviour.
Here's what has worked for
some students.
1. Make a study / homwork time / space. A quiet room, with a desk and supplies and NO access to TV / radio / fridge is important.

For a 9th grader, I'd say 90 minutes of study / homwork (including reading) is probably average.
She has to sit there for the 90 minutes no matter what. If she "has no homework" it doesn't matter - she can stare at the walls if she wants - she sits at the same place, at the same time every day. No matter what.
2. Ask for home copies of all of her textbooks. If you need to rent an extra copy or buy and extra textbook / novel - do it. Now, there is less excuse for not doing the work / reading. She can never say she left something at school. And, if she claims she "has no homework" - then she can use the texts to study.
3. Try as hard as you can to take the emotion out of the situation. Homework can be a control issue, and the more you try to push it / control it - the more she will push back, rebel. I would stop checking her work, checking up with her, etc. The only rule you have is that she has to sit at that desk for 90 minutes every day no matter what. This is the rule that you enforce - if she chooses to sit there and doodle (and she may for the first month) that's fine - as long as she's sitting there for the correct time.
4. Any consequences are hers. If she fails - and doesn't get her credit and has to retake the course - that's her consequence. If she has to take summer school - that is her consequence. I HAVE heard from parents of my children who have moved on to high school that unlike middle school, once they start to not get their credits, and have to take summer school, they do become more motivated.
5. Finally, praise, praise, praise, reward, reward, reward.
Hope any of these ideas help.