Open
Game day was a blast, and the day could not have been more beautiful. The stadium was packed, and I see this picture as open because the stands keep continuing on beyond the edges of the picture.
Thirds
Spotted Afroduck on Mirror Lake, and as he floated away he became off-center in the picture. If you create a grid the subject of the picture falls on the lines of the grid.
Closed
Bikes are very popular around campus (I wish I had one here), and these seemed like a perfect subject for a picture. They are the focal point of the picture so it is closed.
Symmetrical
Thompson William Oxley Statue is a classic here, as he looks across the oval. With the trees framing him on either side and the paths diverging in opposite directions, I see this photo as symmetrical.
Open
The reflection of Scott House in the window of the engineering building made a really cool picture, and the lines in the windows extending off the edges make this an open picture.
Closed, Thirds
Mason Hall of Fisher College of Business looked beautiful with the sun shining behind it. It may not be centered, but it is clearly the focal point of this picture, categorizing it as closed and thirds.