In my observations, and just as a general tendency independent of coaching and mental conditioning, girls tend to be a little more team-oriented; many of the ones I know are just as happy to pass the ball off for an assist as to take the shot, and sometimes more so. The advantage is that they can be more patient and less likely to force a situation and develop good short-passing skills, but the disadvantage is that sometimes they don't take full advantage of pure aggression and kill instinct.
Boys seem to have a natural tendency to want to be the star, and to always want the ball; the advantage is in the aggressive play, killer instinct, and willingness to take a chance at making the play; the disadvantage is that there is more inclination to hold the ball or try to force through pressure rather than giving the ball off out of pressure and put someone else in control, or send an easy shot high and wide trying to rip it through the back of the net when a less-spectacular pass to the corner would easily suffice.
Again, these are just broad generalizations with many notable exceptions, and can be affected and changed by coaching style and mental conditioning.
