No, but my introduction to Fantasy was Jay Williams’ “The Hero From Otherwhere”, which I doubt is still in print.
Oh, heck yeah. I saw that book at the public library and noticed that it was the same guy who wrote Danny Dunn, so naturally I picked it up and read it. It was even better than the Danny Dunn series in some ways. Great book.
Nostalgia overtook me, & I requested a couple of DD books from the library.
They had to dig them out of storage in the Annex. 
Did anybody see the TV show Las Vegas on Monday night? There was a security and surveillance convention at the Montecito, and the beginning of the show featured a guy remote-flying a robot dragonfly with a tiny camera and microphone built in; he was using it to peek at cleavage and the like.
I wonder if the person who wrote the script for this episode was a fan of Danny Dunn…