We have a game in our family called 'red car.' It's extremely simple. All you have to do is be the first to shout, 'red car' when you see one and you score a point. Obviously this is an outdoor game.
Last Thursday we were playing red car when the rules were changed. First my son suggested we play 'red anything' so we shouted 'red thing' when we saw something red. He then went on to say, 'how about we play anything anything, but in our heads silently!!!!!' Of course when you play it that way, it doesn't look like you're playing at all.
My suspicion is that he has grown out of the game!
Anyway today I informed him that I had been playing it for three days and had seen a huge amount of things first and therefore I must have won. He asked me to prove it.