how young is too young to begin grappling\joint locks?

[elbows_and_knees]

judo has a set of official guidelines for kids. They can begin training at age 8. They will learn throws and grappling. at age 15, they can start submissions, but can't choke. at 17, they can choke.

I haven't read the guidelines in a while, so these may be off slightly, but you get the idea. until you reach joint locking age, they mainly drill throws and ground positioning only, as they can't lock or choke in competition.