The average height of a girl is 5'4" And for a guy its 5'6''.... Which is rare because a lot of girls arent that short these days [proof: myself.. Female.. im 5'10''], and that goes for men too... (i think average height for a girl is 5'2)
The average weight of an thirteen year old girl is 101lbs. but that is based on the average height of an thirteen year old girl. If you are taller than an average thirteen year old girl you will weigh more.