you should really learn hungrydragon-san! it's really fun! there are a lot of things to learn especially their alphabet, they have 3 alphabet and currently I only know how to read and write hiragana, there's still katakana and KANJI! blimey! also their sentence structure is different from us, in the sense that their verbs come last unlike in the English grammar. and yeah the disadvantage of what Li-Mei stated is there (if you're learning alone). but don't get disheartened!
it's really fun! lucky you, you get to have lessons! I'm just learning by myself! I have no time and money yet to have formal lessons! even so, I learn basics and something about it here and there. IT'S REALLY FUN!
DAKARA, GANBATTE NE!