A short disclaimer before I begin: this is my first review and as such I may go all over the place, and for that I'm sorry; secondly, english is not my native language so there might be a couple of mistakes here and there.
Now that the manga has practically ended I can safely say that this is a solid story, worthy of your time and that will entertain you.
That being said this manga is not without its flaws, first and foremost the art. As a matter of fact the art is average at best with a couple of good panels here and there, but it's nothing that will drive you away, it just takes some getting used to.
The characters are nothing that you haven't seen before in other anime but, once again, they have some sort of charm to them and they go through some major development (something that you don't always get in this media) so you will surely connect with them. All of them are defined by a specific quirk but the mangaka as been able not to make them the only thing going for his characters, something that usually happens in many harem anime and manga.
When it comes to the story I'll tell you this: it's really fun and entertaining and if you are late to the party (meaning you start this series when it's already finished) even more so.
It starts with the protagonist, Futaro, trying to make the girls study under him and from there you get to see him interact with them and get into all kind of weird situations.
Probably the best way to experience this series is though the manga by virtue of being better paced and more pleasing to the eye (the animation of the anime wasn't very good in my opinion).
Overall I give this series a 7,5/10.
It not a must read but it's surely something valid to read if you are undecided on what to read next.