What got me fascinated in space as a kid was Carey Rockwell's Tom Corbett Space Cadet series, still gracing my bookshelves.
And for Science and Technology were the Tom Swift Jr. books by Victor Appleton II. I had a few of Tom Swift Sr. books from my dad, but identified more with the sons.
Then came Starman Jones (to my attention) and the rest of the Heinlein Juvies and I was hooked for life, planning at the time to definitely go to the Space Academy when I grew up. And my parents even let me join the SFBC in 1956 broadening my horizons. I've been a continuous member ever since.