Here's a fun little post featuring the 'Teenager' Monster Movies from 1957-60. You'd think that there were actually more, but, there are only six monster movies with that moniker!
I goofed up the post by forgetting to include poster and photo from Roger Corman's 1958 production of TEENAGE CAVEMAN, but it's fixed now, read Jonny's comment catching the mistake.
TEENAGE CAVEMAN from 1958 starred Robert Vaughn with Ed (THE BRAIN EATERS) Nelson and Beach (CREATURE FROM THE HAUNTED SEA) Dickerson as fellow cavemen. Swear to God, those hairdos on Ed and Beach are freakin' hilarious as Hell! Hate this movie!