If you are starting at level 1 it is very probably not going to matter what the average age of level 1 gymnasts is because you will probably be put in a class for beginner teens, not a class with assorted age level 1 gymnasts. You also probably won't be at level 1 very long. Also different gyms cater to different markets and run different types of classes. In a serious competitive gym the level 1 gymnasts might all be very young and they might not take teenagers as beginners. Other gyms might focus on the rec side and not really produce competitive gymnasts and then they might have a lot of older girls starting from scratch. Some gyms will have separate recreational and competitive programmes in which case you would probably be put in the rec programme but might be able to move over to competitive later if you have a lot of talent and progress unusually fast. So the overall average age of level 1 gymnasts is almost certainly going to be quite irrelevant to you.
I'm 12 and I just started in level 1, there are 13-14 year olds that are level 1 in my gym as well.
In my gym, they don't put girls on their team over 9-11. Though, it is not impossible to be put on the competitive team. I am a level 5. I started at 13. Most girls are average 3-5 on level 1.
It really doesn't matter how old you are. It's based off of what you can do and what you are capable of.
