Not as scary as an adult, but still *fun* - it has some real suspense and real thrills and actually has an environmental message (great shot of a cigarette butt being thrown into the lagoon... camera dips underwater to show the Creature looking up at the butt and garbage floating in his pool). I didn't notice the environmental stuff when I was a kid, and I wonder if the audience in 1954 audience noticed it. It's *very* apparent when watching the film, now. Horror movies were great places to make a point or explore a theme because they were usually made by the low budget division at the studio and they only cared that they made money. There are many horror films about scientists who fool with Mother Nature with terrifying results, but CREATURE FROM THE BLACK LAGOON is different in that it focuses on an exploration party basically trashing the environment by throwing out their garbage and polluting the natural environment of a creature... who doesn't much like swimming in cigarette butts. There were two sequels that seemed to miss this point... the second film is watchable, the third seems to be mostly guys sitting around a table on a boat talking.
This is one of those films that people my age saw on TV as kids and remember - which is why Universal keeps trying to remake it (earlier this week they hired a screenwriter - David Kajganich who wrote the unwatchable remake of INVASION OF THE BODYSNATCHERS with Daniel Craig and Nicole Kidman). There have been dozens of previous attempts to remake it, one with Will Smith!
The cheese-fest ANACONDA owes just about everything to this film.
For a while there was a slot machine in Vegas based on BLACK LAGOON, and I always played it because it had clips from the film with some clever quips... and that sting.
I have no idea if kids today would find this scary, or just silly - there's no gore at all... but when people dangle their feet in the water and you know it's down there, that scared the heck out of me when I was young!