Academic Shoot

 This is framing because the stair case railing covers the space surrounding the girls in the photo. The subjects are the two girls shaking hands, which you can't see because they are behind the railing.

This is a rule of thirds. Her head would be in the top left of the grid if it were there. The subject of this is the girl putting sticky notes on her book.

This is simplicity because the only interesting thing are Ivy's hands on the keyboard. The subjects are the hands on the keyboard.