I heard "Nothing's Gonna Stop Us Now" on the radio today and thought of Mannequin, and all the fantastic weirdness of things that happened in so many 80s movies. Mannequin comes alive. Robots came alive (Short Circuit). Aliens kidnap kid and then fly around the world with him and there's time travel (Flight of the Navigator). Friendly alien arrives who makes kid's bike and M&Ms fly (E.T.). Kids find buried pirate treasure and mobsters (Goonies). Rich girl gets magically turned penniless (Maid to Order, Overboard -- although the second one involved amnesia). Time travel in a Delorian to make sure your parents GTG (Back to the Future). Ghosts invade NYC and are fought off by funny scientists (Ghostbusters). Little kid gets turned into an adult (Big).
It wasn't just movies like Labyrinth or Legend where crazy, magical stuff happened in a magical world, there was a whole genre of movies where offbeat, weirdo concepts in "real" life were the heart of the movie. I feel like most of those movie concepts would never get greenlighted in movies today, lol. We have tons of super-serious action/superhero movies, dystopian teen stuff and whatnot but that sort of innocent regular-people-encounter-the-fantastic-and-it's-fun-and-funny movies are definitely an 80s thing. Except, I dunno, maybe Hot Tub Time Machine? LOL. I haven't seen that one.
The very first movie that popped into my head was The Breakfast Club
but then I was reminded of Zapped! with Scott Baio - a story of nerds who come up with a telekinesis potion and use it to do what any normal high school kid would - lift up girls skirts and rip open their shirts.
ETA: If you haven't seen this movie and you have some time to really commit some brain power to this deep movie, it can be seen in full here.