Oh god. I can still hear the opening. So darn catchy.
But that's about all that's memorable. It's cute and sometimes funny, but it's usually slow and boring. GA is about five girls and their normal lives in the GA art program at school (it's a slice of life comedy). I find it's a mix between Bottle Fairy and Lucky Star. Very cute and hyper characters who talk about random stuff (usually begins with art) and get insanely off-topic.
Since it's really slow and potentially boring, watching it all at once is not a great idea. Perhaps I would have liked it more if I only watched one episode per week instead of all at once. It has it's fun moments, but the jokes get old when watching it for hours straight.
Overall, it's cute and sometimes funny, and probably okay if taken in small doses. I did get enjoyment out of it. It's very similar to Lucky Star, which I didn't enjoy. But if Lucky Star is your kind of show, I highly recommend this one.