The 400 Blows (1959)

A kid steals a typewriter and walks around Paris in black and white. I think he lives in a small apartment with his mom and her boyfriend (or some kind of "nontraditional" family arrangement that isn't entirely comfortable for him) and he plays hooky and gets in trouble in school. Or maybe he gets in trouble for the typewriter thing? Anyway, they send him to, like, a juvenile-delinquent camp, and he gets interviewed. This movie is about alienation and/or the filmmaker's childhood—and probably Algeria, too, somehow (knowing France).

Fighting off gremlins like Corey Feldman.

The Mouse That Roared (1959)

A small country, maybe populated entirely by Peter Sellers, decides to invade the United States and—because their tiny Peter Sellers army arrives during an air-raid drill—the invasion succeeds. Then there's a car chase on a country road. (During the air-raid drill, teenagers might be dancing to rock'n'roll music.) This movie is satirical somehow, as are all films in which Peter Sellers plays multiple roles. Here's another movie I can't see being much longer than 20 minutes.

Ooh, Jean Seberg!