Make no mistake: Mission! School is a stupid manga. It quickly forgets its own central plot (premise: hijinks ensue as girls trained for combat have to adapt to a normal school setting), and its characters are one-note at best. But it's funny. It's really really funny. And it doesn't have to be anything else.

You see, Mission! School is first and foremost a gag manga, full of weirdos and fools doing silly things in variably ridiculous scenarios, framed as a romantic comedy and peppered with a moderate disregard for the Fourth Wall. In it, we see male lead Ishikawa - a mildly reserved guy (who, as the manga gleefully and excessively points out, has no remarkable features or abilities) - generally play the put-upon straight-man to female lead Haduki, who drives the comedy with her earnest, overeager, and ultimately doomed attempts to do normal teenage stuff in a normal way, in spite of her ridiculously out-there rich-girl upbringing, her insane world-conquest-focused schooling, and "help" from her lazy, self-interested, possibly-sociopathic attendant/friend/classmate Minagawa. A cast of strange supporting characters join in and try to interfere with or aid Ishikawa and Haduki's misadventures and budding relationship, all either starting off as or becoming slaves to the gag-a-minute nature of the manga. And everyone and everything in Mission! School is so sincerely and excitedly committed to its gags (and particular gags, at that!) that it skips right past feeling "forced" and becomes amusing in and of itself.

Mission! School is not a witty manga. It is incapable of utilizing much if any character humor. It doesn't derive entertainment value from situational humor (save for absurdism). No, when it comes right down to it, Mission! School's primary strength is its ability to repeatedly defy minor expectations about what's going on (in the plot and in the characters' heads) in generally stupid ways with vast enthusiasm, perfect timing, and expressive art.

And that's it. As a romance, Mission! School is insubstantial and unfulfilling. As a story, it has no plot, and there's no depth to its characters. Heck, its final volume is 50% comprised of meta-humor about their impending cancellation. As a comedy, though? It's light-hearted, good-natured, and, most importantly, gut-bustingly silly. I laughed often and wholeheartedly.

So what else is there to say that's really meaningful? Maybe it's ultimately forgettable, but I've never smiled, chuckled, and laughed as much while reading a manga. Simple and (perhaps) disposable though it may seem, Mission! School holds a special place in my heart. So maybe you should give it a try!
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Story: 3/10 - It forgets its own premise for the most part and has only the vaguest sense of narrative motion
Art: 9/10 - While not innovative in any sense, the character art is a constant highlight of the work. It is energetic and expressive, effectively adapting its style for whatever suits the gag-du-jour. Comedic timing is controlled with skillful panel composition.
Character: 5/10 - Character development is just about the last priority of this manga, and consistency isn't far behind. Case in point, multiple supporting characters end up abandoning their key characteristics or being forgotten entirely. But, while they may have the level of complexity in their personalities as cardboard cutouts would, oh boy are they fun to watch!
Enjoyment: 10/10
Overall: 9/10