This photo has captured the models mid-action, it contains a lot more dynamics in it and is probably taken by a professional photographer. The background is a good colour and the image is crisp with a good depth-of-field. A good camera was probably used in the capture of this image, probably a DSLR. The outdoor lighting is good and there is no glare or red-eye.
This photo is much more unprofessional, it has probably been taken on a much cheaper camera, possibly just a digital camera, the lighting is not very good and the colours are not very good, the image is not very planned and these are probably not models, it is just a photo taken on an occasion by a family member or friend, it would have been taken for personal purposes.
This photo is obviously about bullying; it is staged and is in black and white, giving it a more serious feel.
This photo is also about bullying, but it has the subject in the foreground and has the bullies out of focus in the background.
This photo is again about bullying but uses shadows to create a different effect. It is the most powerful because of the dramatic effect.
This photo is about bullying but is a shot from behind and this makes it seem more threatening.
This photo shows the contrast between a soldier with a gun and a very innocent small looking child.
This photo is an over the shoulder perspective and it makes it feel much more intimate as well as serious.