My coaching philosophy is to have kids learn how the game really works and why certain things work and other things don't.
My favourite conditioned game is called "No Dribble Forward". Players are not allowed to dribble in a forward direction; they can dribble sideways and back. First of all, this really helps them learn to instinctively get a tight touch to control the ball. Second, it really changes the way teammates move when they know that the receiver of the ball isn't going to just try to bomb forward with it!
I also play pickup soccer at lunchtime at UBC in a game that has existed since the early 1970s (like me!). The average age is usually about 50 and we play to small goals with shooting only from inside about 6 metres.
And I play in an over-40s or over-50s team on some weekends. Good fun, but not the fastest pace!