The Black Market: This is the place to get all your fruit, rare Chao eggs and items to help your chao in ChaoKarate. You can also sell items and he says 'thats a rare item i'll pay you ten rings for it'. I think i once tried to sell my chao but he probably said no. I wonder if you can sell him eggs...
The Classroom: The classroojm helps your Chao's intelligence and whatever he learns in there he does in the chao garden. Your chao can only go to the same lesson three times before he has 'mastered this trait'. The lessons are Cymbals, Maracas, Song, Bell, Tambourine, Drums, Trumpet, Castanets, Spin Dance, Step Dance, Go-Go Dance, Shake Dance, Swing Dance, Drawing, Exercise and Flute. Apparently the lesson changes every 30 minutes and a Chao lesson lasts just 10 minutes.
Chao Principal: The Chao Principal 'Chao Professor' tells you things about Chao, normally things you are likely to already know from the instruction 'booklet'.
Chao Doctor: The Chao Doctor shows you the main strengths and weaknesses of your Chao with the Medical chart. When you show him to the doctor he says 'he's fine, come back when he's dying of the plague', well, along those lines. Try showing him an item, haha what a fool.
Fortune Telling Place, Thingy: You don't get your fortune told here but it's a great place to get a name for your Chao. If you want to make your own name up say, No to the name she gives you and No to another name then Yes to name it yourself