Rainbow Bikes

The school has many different kinds of bikes but the he kids are always fighting because they all want to ride the Rainbow Bikes.  The Principal, teachers and school staff can't understand the problem because they don't see any real differences between the bikes.  When they ask the kids why they only want to ride the Rainbow Bikes, the kids response is that they are the fastest bikes! The Principal, teachers and staff decide to test this reason for themselves by racing the various bikes themselves.  When the race is not won by one of them on a Rainbow Bike, they know that being fastest is not the real reason.  The teachers then ask the kids several more times to tell them the real reason why they prefer the Rainbow Bikes. Each time, the adults try to confirm the reason and none of the kids reasons can be confirmed.  Finally the kids convince the school leaders that, if they sell all of the other bikes and replace them with Rainbow bikes, the conflicts will end.  When all of the Bikes have been replaced with Rainbow bikes, the fighting ends.  But the adults still don't understand why the kids prefer the Rainbow Bikes.  Only the kids know why!