If you're a long-time anime fan, you surely remember those 2000's romance anime full of ecchi, stupid jokes and a incredible strong love. Kishuku Gakkou no Juliet is just like that.
Nostalgic because of its resemblance with the anime we watched during our younger days, Kishuku Gakkou no Juliet may be seen as something good, or at least tolerable to watch, when it's not.
Sure, maybe the relationship between the two main characters is cute and all that, but it's not worth the watch when everything else (other characters, plot, setting) is plainly mediocre.
The opening deceives (It deceived me) and make you think this is an actual good anime, but it's not. I guess some episodes are fun, but overall it's pretty weak.