Actually that last one is what they call the "sorority squat." All the sorority girls pose that way for pretty much every picture they take with each other. Squat down slightly holding that pose and fold hands on legs then photo time. Google it
And if you ask me the first one is just a poorly planned abdomen line. The cheerleader is pretty raunchy though, the only thing I can think to justify it is she's running her hand down her skirt to keep it straight and not fly up
Okay, obviously the girl in the first image broke her nail and doesent have any pockets so she had to improvise to hide it... At least that's what I'm guessing, I could be wrong XD
It's obviously her other thumb in her belt but hey we can still make jokes about it you bunch of grumpy people.