I felt that this book started very, very strongly - enough so that I ordered up the 3 sequels when I was only about a third of the way through it.
Unfortunately, I felt that as the story progressed, it got much more formulaic - a group of young people are brought to a magic school by a mysterious but wise mentor, and each discovers that one 'element' of nature is their particular specialty, as far as magical talent.
Feel like you might have read something like that before? Probably.
However, the tale-telling is both charming and entertaining enough that I do plan on reading all 3 sequels. They go quickly, too.