The character looks really good. She looks like she's going to be sporty and bold and it's good you've managed to capture that. Her hair is cool, seems to fit her well and it's nice that you're done lots of smaller strands. The colours you've used are also nice.
Crits (hope you don't mind):
The mouth is a little too far up the face. Anime takes alot of liberties with facial features but usually it would be somewhere underneath the nose and if off center, then off centered underneath the nose.
The neck, because we are facing her dead-on, wouldn't go into the body I believe, it would naturally curve out into the shoulders (so no lines cutting into the body), I think when the neck cuts into the body is when you're facing above the character, and then usually the rest of the body goes somewhere behind that, by a considerable amount, due to the overhead position allowing you to see more.
I think the arms, I'm not too sure, but the top half of the arms seems to be considerably shorter than the bottom half.
Also the fingers seem a little too long, and rounded. Thinking about how bones in the fingers go, you may have to make them a little more angular. Also remember the flat of the hand and account for it. I think where the thumb joins the rest of the arm would be more curved, I'm not sure, maybe something to check in a mirror ^^;;
The clothing design is cool, and as I said, the colours are nice. I think you need to consider folds more though, and how they fall and shape. It adds a whole new dimension to characters, even if it is hard to get a grasp of at first. Maybe research up a Google.com pic of a Japanese uniform on a girl and see how the folds fall. Especially if you're doing skirts! Skirts are soo hard (for me anyway), getting the folds right on skirts can be difficult but it's worth it to get clothing that flows around the character more.
Light would also be bouncing off the skirt and because of the folds, there would be areas considerably darker than others.
You may want to consider using the circles and shapes method for determining the shape of the head and body. I rejected it for quite awhile, because I didn't think I'd want to use silly circlesetc. However it is what proper animators use and once I started to use it I realised how helpful it is. It helps give you a rough idea of where to position parts of the anataomy in a simple and easy way. There's an example of the circles/shapes method here:
http://www.howtodrawmanga.com/tutorial/tutorial.html
And one for heads here:
http://www.howtodrawmanga.com/tutorial/tutorial.html
Anyway as I said it's looking really good, just need a few things tweaking.
Hope I helped.