The quality of being instructive; power of instructing.(noun)
The Century Dictionary (Public Domain)
Use "instructiveness" in a sentence
"I think it's important with Wayne because he's sort of an everyman and, you know, his music is down and dirty, but there's always been an element of instructiveness to it."
"I believe, moreover, that the boredom of such a book would match its instructiveness."
"Back on deck I press the instructor about the instructiveness of all of this."