For real, her lips are ALWAYS PURSED!
Seriously, though.
It's kind of a classic shoujo manga. You've got your female protagonist and your 2 love interests: the dark moody guy and the cheerful bright guy. Then you've got your best friend and that's pretty much your whole main cast. Different things happen to the main characters, and slowly, the characters' friendships turn to romance and love triangles.
Characters: 4/10
One difference is that the protagonist is not some ditzy girl, who knows nothing, or some crazy strong girl, who knows everything. She's not your classic protagonist. Instead she's the sort of character that would usually be placed as the main character's best friend (kind of similar to Hana from Fruits Basket), calm, cool, and collected, not caring what other people think, not nearly as expressive or emotional as so many shoujo characters tend to be. In fact, not really expressive or emotional at all.
Personally, I didn't like her as the protagonist (I found her a little boring) and I think that sort of character is better off in the best friend position, but I appreciate the attempt to do something different, and I'm sure that there are some people who really like the main character.
Actually, I found myself connecting most with the best friend
who is in love with Maria's main love interest
and the less likely love interest, which kind of sucks, because now the two relationships I ship are the two that are less likely to happen . . . but again, that could be just me. You might really like the canon romance.
Art: 9.5/10
The art is very beautiful, in a modern shoujo way, which I always find very important in a manga
Plot: 4/10
Like I said before, classic shoujo manga. Not much else to say, plotwise. It involves music, I guess, and musical performance, so if that's important to you, then you should like it. Um, it also has a bit of the classic "mystery past" going for it, which always makes a story more interesting. But in the end, it is what it is, and what it is is okay, but nothing unique. Read it if you've got nothing else to do, but don't expect to find any certain amount of depth or anything.
Rating so far: 6/10
By the way, I complete agree with fictionalscience's comment that the students and teacher are unrealistically mean. Especially the teacher. If a teacher acted like that in real life, he would be fired. End of story.
It seems very naive of the author to have the teacher act so childish and the main character act so adult, as if she's trying to make a statement about adults not always being right or something. I'm not saying adults are always right, because they're not, at all, but this does feel too similar to the mentality "I'm being a rebel for the sake of being rebel". In other words: "My characters are going to be unrealistically a million times more mature than their teacher so that kids today will connect to them!" Adults who write stories like that just annoy me.
Deduct 1.5 points for unrealistic bullying