This is another one of those shows which you find out about through a random recommendation, and it ends up being one of the best things that has ever happened to you. Sket Dance may not be very popular, but it's definitely not one to miss.
The story revolves around the three main characters: Fujisaki "Bossun" Yuusuke, Onizuka "Himeko" Hime and Usui "Switch" Kazuyoshi, who are all members of the Sket Dan - a club dedicated to helping anyone in need and solving their problems. Unfortunately for them, their lack of requests usually leaves them lazing around their clubroom on most days, or at the very least, doing odd jobs around campus.
On the surface, this show seems like a typically 'optimistic' Shonen series, delivering a message about assisting others. However, watch one episode and you'll realise that it is NOT what it appears to be. The series is filled with humour, usually revolving around parodies of famous shows and personalities, or language-related gags. A word of advice - this series is best enjoyed by those who have already watched a lot of anime previously, and/or read a lot of manga. Most of the gags can be appreciated if you know anime and manga stereotypes or cliches, as this series deals with them constantly.
The animation and artwork is not special in any particular way, and yet it just seems to fit the mood of the story perfectly. The characters' expressions change constantly, and are consistent with the art of the manga. I would love to give examples here, but I won't for fear of spoiling the series for anyone who plans to watch it. All you need to know is that the animation is beautiful in its own way.
The opening and ending themes are good, although I personally prefer the ending theme. The opening is pretty misleading, though that's not necessarily a bad thing - it depends on you. The background music does not particularly stand out, but blends brilliantly with various scenes without seeming overdone. The voice acting, however, is AMAZING. The characters are all brought to life by their respective actors, and they do an incredible job.
Despite the art and humour being good, they would be nothing without a strong cast; which is exactly what makes this series stand out. The characters are easily the selling point of Sket Dance. The incredibly-popular otaku Switch, the intimidating Himeko and Bossun with his 'amazing power of concentration' make for a perfect star cast. The supporting cast includes a samurai, a creepy girl interested in the supernatural, and a Shoujo-manga artist wannabe who sees the world through an 'Otome Filter'. These are easily the most varied characters I have come across in a single series, and yet the bizarreness of it all makes it even more entertaining to watch.
Sket Dance may not be a series for those new to manga and/or anime, but for most 'veterans' it is a must-watch. Once you're hooked, you'll never want to let go.