I shot a couple of senior sessions last weekend. Both kids wanted sports related images. On the first three we had to squeeze it in between church commitments and team films - which put it in the middle of the afternoon and there wasn't a cloud in the sky.
The second set is actually my nephew - he got ansy to take off to a party when the sun was just starting to set and give us some color in the sky. Fortunately I got his to stick around.
Mark: I don't have much experience with this type of shooting so I'm just firing from the hip in providing feedback. #6 is my favorite of the set, followed by #10. #7 is pretty cool, and there's probably more meaning in the selected background than I'm aware of. #'s 2 and 3 don't work for me because the background is too murky--something's just off with those shots. #8 has promise and takes full advantage of the sunset, but I want to see him in the right third of the frame, not the left. Looks like you've got plenty to work with here.