Story: The story is rather jumbled in this anime. It's basically Itoshiki getting to know his class of rather eccentric students while at the same time trying to teach them about the despair of the world. His attempts to spread his pessimism is thwarted by Kafuka, the eternal optomist and several other members of the class. The story itself leaves a lot to be desired, but the humor and situations make up for the missing plot.
Animation: The characters themselves are simply drawn, with certain features, a bandage, the perfect center split of Chiri's hair, seperating their rather similar faces. The background and landscapes often draw the eye away from teh characters, such as the beginning scene with the cherry blossoms. And I don't know if it was the version I watched, but there was a guy's face on the school clock and blocking every ecchi occurance (except Kaere's characteristic pantsu shots).
Sounds: Between the OPs, the ending song, and the interlude of melodies, the sound was superb. I loved the ending, Zessei Bijin, enough that I listened to it on repeat for quite some time. It's rather catchy.
Characters: Oh lord. I was wondering how many character quirks they could stuff into one anime. Apparently, the answer is "A lot". The eternal pessimist Itoshiki holds the main lead, despite the girls of his class vying for the spot light. Each one has their own quirk, from a perfectionist to a foreigner to a tail-pulling animal lover. The little quirks give each girl a name, but not much room for further development. While Itoshiki learns a lot from the girls, I have to wonder how much they actually learned from him.
Overall, I liked this anime. It's quirky and insane and brilliantly done for a slice-of-life.