DD is 12, she is currently swinging a demarini cfx 31" drop 10. It is 2 years old.
Her coach recommended we start looking with a 32-33" and a drop 8 or 9. Isn't that a really big bat? DD is 5'3" and 130 pounds, or around there. We will have her try out bats, but I assume there are limited bats available to try, far fewer than the million online. I don't mean to question her coach, but it seems drop 8 and drop 9 are far less common than 10 or 11. DD is strong. Regular 12 yo strong kid kind of strong, not hold the phone kind of strong.
How does bat balance contribute?
First as children grow bat length needs to be increased to cover plate correctly. As an umpire I can always tell when the bat is too short for the batter. At 12 I would guess 32. If she is 5'7" think 33. As for weight it is more about her swing and her strength. If she is late drop 10. I would go drop 9 although the difference between 8 or 9 is minimal. I will not recommend a mfg. or a price but if she gonna stay with this listen to coach and give her good tools. Enjoy....