"The Adventures of Superboy" was a TV pilot produced in 1961, fresh off the heels of superhero fever and the personal blessing of DC Comics editor Whitney Ellsworth, which should have spelled success for this adaptation of the popular hero. Instead, "The Adventures of Superboy" stands as a weird appendix, in the anatomical sense, to the "Adventures of Superman" program that had so many audiences loving George Reeves after it aired. John Rockwell would play Clark Kent in his Superboy years. Yes, there is a period in the comics where our Man of Steel was more "Boy of Tomorrow." Superman's mythos is complicated, and shows like this make it easy to see why.
Interestingly enough, the popularity of "Adventures of Superman" was the primary reason that "The Adventures of Superboy" ever even got to the pilot stage, in contrast to our recent entertainment climate, where you might have that spinoff without any real Superman on-screen to anchor it. The reasoning is sound, but things still went a bit awry in that way that Hollywood can produce from time to time, and the result is "The Adventures of Superboy" being more a "Jeopardy!" question than an actual artifact.