Globetrotting Boy Detective by [[Jerry Michalski]]

Also in this pantheon, though later, are Where in the World Is Carmen San Diego and Wild Kratts.

The Mad Scientists' Club was in the genre, but with less globetrotting.

https://www.amazon.com/100-Fathoms-Under-John-Blaine/dp/B004J0V01A<br /> 100 Fathoms Under by John Blaine<br /> Grosset & Dunlap, 1947