I adore this photo professional photographer Derek Heisler took of our favorite, and probably longest-running, science professor Bill Nye, for many reasons. One aspect that Heisler has mastered here is the depth of the photo (thanks to Nye's quirky pose). It gives the photo dimension, depth and creates interesting angles. Another feature are the colors and choice of lighting. The dark on dark don't detract from each other here, luckily, but rather work to draw in your attention to look closer. Heisler also paid attention to the "rule of thirds."
It took me a few seconds to fully appreciate this photo by Benjamin Morris. In capturing the 2011 Pan American Games pole vaulting contestant, he instead focused on the shadow created by the athlete, rather than the athlete himself. We are able to understand exactly what this photo is of despite the lack of visual context. That is what makes this photo so creative and memorable. The shadow's placement within the photograph also adheres to the "rule of thirds."
Now this is another image focused on the feet and the shadows created by the young boys' legs. However, I don't particularly see the purpose in focusing on these boys' feet rather than their faces. I think their expressions would give this photo a lot more meaning and add the necessary context. Also, the one boy's leg on the far right is moving and, thus, blurred. So, first, I would direct the camera upward and capture the boys in their entirety. Second, I would make sure no images within the photograph are blurry. Third, I would've tried to stand in a position where the shadows of the boys could tell a better story than the dull one they're telling now.
There are quite a few suggestions I have for this photo by Dan Brandenburg. Most importantly, there is just far too much going on here. It's okay that the people aren't facing the camera, but they're just stacked throughout the photograph randomly and the viewer is unsure of whether the focus should be on the monument in the background (which I'm assuming it should be due to the vertical position of the photograph). My other biggest problem with this photo is that it doesn't capture anything besides a not-so-organized moment in time. There's no mood or message the photo evokes or sends. We can't even adequately guess at why they're all wearing the same green shirt. So the three improvements I would make to this photo are to find the focus - either the people or the monument, make sure my photo tells a story, and beware of crowding and awkward placement within the photograph if you do decide to photograph a group of people.