I have a chicken and egg delimma with responding here. I don't know whether DS8 is a substantially different kid, or if my style has had an impact. But there are rarely free answers in our house unless it is purely an expedient thing. DS doesn't ask a lot of factual questions, and knows to take a first stab at something. This has its downsides as he doesn't want to be told things unless he's fresh to a topic (or it's spelling.)
So, in the long run, I ask more questions than he does. He gives me answers to things he's wondered, and he gets praise in measure to the effort he put into it and has pride in it.
