Overall, the second one is the best one, but I feel they are all a bit dark, and the backgrounds are too cluttered (except for #2). I would like to use some fill light (not necesarily a flash, but at least a reflector) to brighten the main subjects, and would choose my background more carefully. I also find that for most skateboard tricks, sequences work better, as it is hard to understand what is going on (what the trick is) with a frozen image (except for rail slides down handrails or similar, and jumps, either vert or launch ramps, which tend to look great as a single image). I would also like to get a grittier look to the images, as it lends well to the subject. Anyway, that's just my 2 cents, and I doubt I would have gotten better shots if I tried myself... The last time I took skateboarding shots was about 16 or 18 years ago!