help me find a movie

I am looking for a movie, I watched the genre of youth erotic comedy
on video cassettes, it was called Lucky, the year of creation was until 1989-1997 approximately
Plot - The bespectacled loser at school became small and got into underpants to the main beauty of the class who rode a bicycle
He earned money by wearing towels in the gym and he was nicknamed the towel man.
There is a scene where he also poured water on her and the guy who was the main bully in the class, when he tried to take off her panties on the lawn.
He also tried to get out of her panties when he became small, at that time she was sitting in class and finished.
That's all I remember
Thank you if you help