The number one reason kids do anything is because it is FUN!
Everyone at any level including adults play sports because it is FUN! As we get older we tend to forget the fun element while we stress how important winning is and we adopt a win at all costs mentality. I guess it is our American culture that dictates, "nobody remembers second place". Notice, any pro athletes that give an interview after a game that they won; they always mention that the team had FUN! Teaching kids to have FUN while emphasizing fundamentals though FUN games it is a habit that will stay with them all their lives. That is the main reason why I love Brazilian style soccer. They play because it is fun, and it shows in the way they approach the game, the creativity on the pitch. Brazilian style training, although tough is full of FUN games emphasizing fundamentals, footwork and agility. The foundation of the body is your feet and if you are light, quick and durable on your feet you have an edge over the rest of the players. More and more trainers start training the kids at a young age, not only fundamentals but also how to move their bodies and feet. I found this training system that I have been using with my U8 teams as well as U12 and U14 kids.
Fun has no age limits. http://www.soccertoplay.com/futworks.html
I plan on using this with everyone regardless how old they are. Hope it helps you as much as it has helped me. Remember a daily dose of FUN in everything we do not only puts a smile on our faces, it encourages to keep doing what we are doing deriving at better and quicker results.