This afternoon, my wife and I went to a tae kwon do gym to watch my granddaughter learning that martial art. There were many kids , about five to eight, learning the fighting skills of Korean style. All the kids were only playing the game with fun but in an attentive manner. My little girl was pushing five, so she must be in the preliminary grade. There is a long way to go, even just for the purpose of exercising or learning defending skills. It depends on her propensity and her parents affordability.
The instructor can kick her foot as high as over her head. I asked my granddaughter if she could do the same. She showed me: reach her neck. Well, not bad.