Ren'ai no susume

In this series it starts with the smartest kid falling into a shallow puddle of water and being saved by a pretty girl from another school. He then proceeds to try to win this girl over as he has feelings that he never had before when it comes to the opposite sex. The principal who is the father of the boys best friend uses his son to try to get the boy to not pursue the girl and later on uses the son to convince the boy the dissuade the other students from pursuing their love interests. In the end the girl helps him get back into the school and he tells the students that it is okay to fall in love and that the school should change. The father tries to dissuade but his old nemesis was there and told everyone how he was once in love as well. The school wound up changing and everyone was happy. This is a nice and clean story and I recommend it not too much drama but enough to make its point.