Move to Dubai with school-age kids?

Considering move to Dubai with two boys, the older in 4th grade. Two concerns: School - they are in top-tier NY schools today and do well on private school tests. How well do the better American schools in Dubai compare to the best schools in the US? Life outside school - a bigger concern, especially as they approach teen years - how have parents been successful in finding sufficient healthy outlets for their teenagers in Dubai? I am already assuming that my kids will be back in the US for summers. Thoughtful replies much appreciated!