When winter fails to provide an adequate snow base, my boys bring their sleds in the house and ride them down the stairs. Just the other day, my wife found them with a rope out their second-story bedroom window, preparing to rappel down the side of the house. The recipe for fun is pretty simple raising boys: Add to any activity an element of danger, stir in a little exploration, add a dash of destruction, and you've got yourself a winner.
John Eldredge (2011). “Wild at Heart Revised and Updated: Discovering the Secret of a Man's Soul”, p.13, Thomas Nelson