It’s classed as an adult novel??? That surprises me greatly. It’s only 128 pages long and features a nutty mutant sidekick. As an adult novel, it’s a lesser work.
Well I did not set up the poll, but as it was not officially one of the Juveniles, I guess by default it went to the other poll.
Here is the list of the The Scribner’s juveniles and the girls’ stories.
Yeah but by the measure Heinlein’s Juveniles are Scribner’s Juveniles, “Podkayne” isn’t a juvenile either. Which is ridiculous of course. Where the correct definition of a juvenile – “book written for a teen/pree-teen audience” – is applied “Orphans” clearly qualifies.
I OBJECT, your honor. 
I had a hard time choosing, as I liked just about all of the books. Farmer in the Sky, maybe not as much, and Rocket Ship Galileo, being his first, was not the best. But as a young person I enjoyed them. RSG had what was perhaps the first Jewish character I’d ever noted in the books I’d read up until then.
OotS was written in the early '40s, before there was a separate market for juveniles in sf (out side of Tom Swift, I suppose.) Where it was published was not an issue - Citizen of the Galaxy was serialized in Astounding, and the Star Beast was serialized in F&SF for two examples.
I love Podkayne, but Star Beast is my other favorite.