My 11-year-old. Doesn't require drugs, just "Go natter about the Franco-Prussian War somewhere else, Pat. I'm sure the cats are interested."
At issue back then was that he got bored easily with 3rd grade work and just wouldn’t fill out the stupid worksheets. So we used adrenaline instead of ritilin.
He got a BS in geology but is now a professional musician. Go figure.