As a ‘preteen’ I took a self defense class with one of the most well known instructors in the country for a style of karate called Ketsu Ka. It focuses on self defense and gives real life scenarios that you have to prove in the belt testing.
Examples:
Someone grabs you by the hair from the front or back
Bear Hugs
Choking
If someone grabbed you by a limb and attempted to drag you
How to get out of pretty much any common hold or grab by an attacker
How to defend another citizen if they are in trouble (without becoming a victim as well)
How to defend against knives, guns(at close range), bow or stick, and a number of less known weapons.
I made it to my Green belt and was testing to get my Purple and I am sure that if I had to get out of a situation where someone was grabbing or attempting to take me I could put up a great fight.
(Size doesnt matter- I used to put down men twice my size and weight while sparring.)