You're doing a superb job with poses. Pressing the shutter at the right time is the most important thing, and you've got that down. Everything else is just fiddling around, minor crap. The nice folks on TPF might, just possibly, disagree with me a trifle on this point, but anyways.
All of what follows in my opinion, your mileage may differ. If there's an idea in here that you like, keep it, put the rest aside:
You're overprocessing everything. They're way oversaturated, the yellow cast looks weird. Someone suggested you've oversharpened the eyes, which certainly looks possible to me.
I know you like it, you're trying an effect out and you're thinking 'crap, that, that looks GREAT! I should do it MORE!'. Everyone does this. What you really want to do, though, is apply the effect, think 'crap. that looks GREAT!' and then back it off by about 50%. Yes, it looks GREAT, you're right. Which means that it's a good thing to do, to get the look you want. But don't do it so much that the effect itself dominates the picture. Saturation is a fine thing -- but the picture is about the kids. Saturate, but back off just before it becomes noticable that you're saturating.
Sharpen the eyes, but back off just before you can tell that the eyes are sharpened. You can still see all the effects when you flip back and forth between the original and the processed, but you CAN'T see it if you just look at the processed image. Now the picture is about the kids, not about the processing.
Make sense?