As the name implies this LN series is all about crazy school girls. If you like that then you might like this series, if you don't care about that then you probably won't care much about this series.
Story (7): Each volume has the protagonist getting involved in a series of crimes that can be quite disturbing at times. He is not the sharpest tool in the box but luckily he gets help from a girl who used to be his knight in another world and her friends so in the end they usually accomplish what the incompetent police force fails to do.
The mysteries aren't very
mysterious because the novels tend to focus more on the character interactions but because of the nature of the crimes they are still enjoyable to read.
Prose (art score) (6): I'm still learning Japanese so I'm not an expert on the subject but the prose didn't feel very inspiring. Part of it might be because it's written in third person and I tend to prefer first person.
Characters (9): The characters are what made me like this series. Juuzawa Juu, the protagonist is a fairly boring simple minded guy. Because of that he pairs very well with the unpredictable main heroine that can show up anytime claiming it's their bond from the other world guiding her. Many of the other characters he meets including some of the villains are equally irrational which provides for many lines of entertaining dialogue.
On the negative side the characters can be a bit one-dimensional so if you desire complex characters you had better look elsewhere.
Enjoyment/overall (8): As light entertainment Denpa-teki na Kanojo is a nice series, just don't expect anything more than that.