Wonderful black and white photograph. You’ve captured a wide tonal spectrum which is what was asked of you from this assignment. You have dark shadows in the brick wall behind the subject and you even hard dark black in the wheels of the skateboard which ensures that you push the end of the tonal spectrum deep into the left end. On the right (light) end of the spectrum you have both the sun’s reflection on the subject’s t-shirt as well as the vibrant white strip running up the skateboard.
My main concern with this photograph is that there are a lot of grays in the image. I think the image may have been more dynamic if you played with tonal balance a little bit. Right now you are about 50% dark and 50% light tones, which isn’t wrong, but it doesn’t strike me as really vibrant. I think it’s because a lot of the tones in your subject are the same (i.e. their pants, their shirt and their skin color are all roughly the same tone).
Try experimenting a bit with tonal balance and strongly slant your composition towards to be either low key or high key. As I’ve mentioned, it’s not wrong what you done, but I hope to see you experiment with tonal balance a little more.