I find it rather curious that this isn't more popular. The following three paragraphs will talk about my experience before watching this anime, so you can skip that if you want.
I discovered it reading a post by an anime veteran (1200+ watched) in a gaming forum. There was some discussion going on about the current state of anime and he used Gokujou Seitokai as an example of an school comedy without any trace of fan service. I thought I should give it a try and tried to download it.
I said I tried to download it because I didn't know this was so rare when I tried to find it. I tried to get it via Torrent but none of them had seeders. I got a few torrents from the most popular anime sharing sites, and after over two months, someone appeared in the seeder list and I started to download it.
At this point I forgot about the non-fanservice thing and just wanted to watch it because it was so rare. Even you search about it in Google, you won't find much. The IRC channel of the only fansub you can find that subbed Gokujou Seitokai, 3WA Subs, is empty. I was really curious to watch this. I didn't expect it to be good, I just wanted to satisfy my curiosity.
I started this review saying that I didn't know why this wasn't popular. After watching just a few episodes, I was surprised that this unknown show I've heard about in a discussion forum was so good. The best word to describe Gokujou Seitokai is "enjoyable". The episodes are really enjoyable to watch. They have an air of innocence and comedy that doesn't exactly feel unique, but the combination of everything creates a really good experience.
The main character is Randou Rino, a young student that has nowhere to go after her mother died of an illness. At this point, her only 'friend' is a puppet she calls Pucchan. Following a letter written by someone who identifies himself as "Mr.Poppit", she heads to the Miyagami School, and meets the Gokujou Seitokai.
The Gokujou Seitokai is a student council that has more power than the school staff. They are considered fantastic by the school students and everyone loves them. They have all sort of unique members that resolves all kind of problems that may happen in Miyagami School. Being invited by the Student Council president and founder Miyagami School, Jinguji Kanade, Randou Rino joins the Student Council. The episodes usually follow her and the other Gokujou Seitokai members as they resolve all kind of situations.
That anime veteran was right when he said it had no fanservice. We are so used to it that it feels strange. There is no fanservice at all. This is a school comedy without a single panty shot in the whole 26 episodes. The characters aren't unbelievable cute, they look normal instead. I know fanservice is not just sexualizing characters, but I don't believe you can find fanservice in any other form as well in Gokujou Seitokai. I don't take this as an necessarily good point - fanservice can be either good or bad depending on the situation and if its needed or not - but finding an anime of this genre with none at all was very interesting. Even if you don't like the genre, I'd recommend watching it just for the reference.
What makes Gokujou Seitokai so good is the experience from the viewer's point of view. While there isn't that much positive to talk in the sound department and even less in the visual (actually, there are some really ugly scenes), the episodes are so well made it makes up for everything. The stories are fun and innocent, simple jokes and funny, unrealistic situations will make sure you'll have fun watching this.
You should watch Gokujou Seitokai. Its an unknown, underrated, wonderful experience created by simple yet wonderful characters and a charming atmosphere.