Football is identified by the World Health Organisation as one of the best ways to keep fit.
Start your children at an early age. Most football academies accept boys and girls at 4/5 years of age. Manchester United Football Academy is a popular with the kids and is based at Dubai Sports City.
Get your children used to wearing shin guards. The ground can be hard and the tackles not very accurate.
Consider getting you child in one of the many junior leagues. Soccer kids Dubai run coaching and mini leagues hand in hand.