Some links:

http://www.theage.com.au/victoria/karate-kids-get-lesson-in-fighting-back-20130531-2nhgm.html
Quote:
This week, an 11-year-old girl in Greensborough thwarted what police said was an attempted abduction when she kicked her would-be attacker as he tried to drag her into a vehicle.


Kids MMA


https://theconversation.com/karate-kids-should-we-be-worried-about-martial-arts-in-pre-schools-12299
Quote:
Pre-schools, childcare centres and parents need to ensure that instructors have the right qualifications and experience.....children learn in different ways and at different rates. They need an environment that is deliberately and skillfully created...