High school and comedy? So tu want something más like slice of life? Here are some i think tu will like with comedy: -Ouran High School Host Club (but i bet somehow tu already watch it) -Special A (Similar somehow to Host Club) -Itazura na kiss (Which is also Shoujo) -K-ON! ( From what tu asked, this one is perfect for you) -Kachou Wa Maid-Sama! (Also Shoujo) -Acchi Kocchi (Really funny) -Lovely Complex (One of the most hilarious animes i have ever watched, it also has shoujo) -Sukitte Iinayo (Huge in shoujo and romance) -Kimi ni Todoke (Romantic comedy)
Now high school, comedy and fantasy! (some of them might have romance o action) : -Sakura Card Captor -Shugo Chara -Gakuen Alice -Fruit Basket -Soul Eater --Kokoro Connect (It has funny parts but also has drama, also supernatural)
And i personally really like To Aru Kagaku No Railgun, which is a side-story of Toaru Majutsu no Index. But tu don't need to watch it in other to watch To Aru Kagaku no Railgun, but both are great.
I always like watching ongoing series because it gives me something to look foreword to each día so I thought I should tell tu about my favorito! ongoing series'.
Gokukoku no Brynhildr - Sundays Hitsugi no Chaika - Wednesdays Mahouka Koukou no Rettousei - Saturdays No Game No Life - Weenesdays Sidonia no Kishi - Wednesdays Medaku City Actors - Saturdays Kamigami No Asobi - Saturdays Captain Earth - Saturdays
Now for some completed series
-Bleach -Naruto -D. Gray man -Fullmetal Alchemist* -Soul Eater -Gurren Lagann -Death Note -Blue Exorcist -Kiba -Tiger and Bunny -Broken Blade -Naruto/Naruto Shippuden -Attack on Titan -Sword Art Online -Hakkenden: Eight perros of the East -Persona 4: the Animation* -One Piece* -Devil Survivor 2: The Animation -Karneval -Hunter x Hunter -Nobunagun -Noragami* -Buddy Complex -Hamatora: The Animation -Strike The Blood -Beyond The Boundary -Tokyo Ravens -Z/X IGNITION -Pandora Hearts
Edit: I forgot to look at the descripción to see what tu were looking for. The shows above are pretty much all action/adventure but almost all of them have comedy in them. I'll mark the ones with the most comedy with an *. So here are some of the shows in the genre you're asking for.