Encino Man

During the first ice age, a caveman attempts to make fire with his girlfriend. An earthquake causes a cave-in that buries the two of them.

This segues into a present day Los Angeles earthquake that awakens average teenager Dave Morgan. He, along with his best friend Stoney, strives to attain popularity in high school but comes off more as a reject and an outcast. Dave is in love with Robyn Sweeney, a sweet and attractive girl who has been his best friend since grade school, and, until she reached adolescence, had been rejected by Dave on several occasions. Read more on Wikipedia.