I stumbled upon Yuyushiki searching for something similar to my high school/SoL/comedy favorite, Azumanga Daioh. So I gave this a shot. And I watched the whole thing through. Does that mean I liked it? Well... let's say I did, but...
We have three high school friends: Yukari, Yuzuko and Yui. Yui is mature and rational (well, most of the time), but the other two are everything but that; they're silly, random and pretty weird. They talk about most random things, that sometimes lead to pretty banal conversations.
Okay, so what did I like about Yuyushiki? First, it's the cuteness of the girls, especially Yukari, who's my favorite. Then, it's their ability to make every conversation silly and funny. Even when they talk about dark themes such as death, it doesn't seem as dark as you think it should be.
Another thing I liked is the educational part. Being members of the Data Processing club, the girls reveal some interesting information about various topics (planets, animals, food, etc.) that you might not know.
What did I not like? Definitely the fact that this anime sometimes gets too weird and/or random for my taste. At times it's just awkward. The relations between the characters, both main and supporting ones, aren't clearly defined. The yuri element is also present in some episodes, but it's very mild, and in my honest opinion, completely unnecessary. And that comes from me, a yuri fan.
Speaking of character relations that aren't defined, their teacher also confused me a bit. She's their teacher, but they keep calling her "Mom"? I'm not sure how common is it in Japan, but to me, it seemed a little odd.
So, in short: not bad "cute girls doing cute things" anime for those who like that sort of stuff. If you don't mind lots of weirdness, randomness and general silliness, give it a shot, you might like it. And you might learn a thing or two about planets or animals on the way.
