I noticed that alot of your shots have alot of headroom meaning there is lots of space between the top-end of the frame and the top of the person's head. This is why the legs are cut off in many of your shots. If you can fill the frame more, you can capture the legs too! Unless you're aiming for a 3/4 body portrait, cut it off before the knees.
Otherwise, composition and focus seems good, I like the "flower frame" one. Just a tip or my preference: only post shots that you're proud of on your page, put other shots elsewhere (I saw a shot with eyes blinking ^_^" in there!).
TLDR: Fill the frame!
For moving/jumping subjects, aim for the highest shutter speed possible, and LOCK focus on your subject before taking the shot, and turn on continuous shooting on the camera so you can take multiple frames by holding down your shutter. You can also do this on single shot mode if you keep your finger on "half-way" shutter so the focus doesn't change when you "spam" the shutter multiple times. That may be too technical