I have an assignment for photography class, and I can’t come up with any original ideas. The assignment is to take pictures of all the same kind of thing, and put them into a collage- but, to make it unique and interesting, you are supposed to throw in one unrelated picture. An example of this would be having 7 or 8 pictures of flowers, and one picture of a fish. I can’t think of anything really original and interesting. Could someone help me brainstorm some ideas. What I’ve come up with so far (admitedly not the best ideas… :P) are listed below.
All pictures of animals, and one human
Pictures of food, and one picture of silverware
All pictures of trees (no leaves) and one picture of an evergreen
Pictures of kids, and one of an adult
Pictures of cars and one of a motorcycle
All pictures of bicycles and one of a car
That’s about all I can come up with… I would greatly appreciate it if you guys would help me come up with some better ideas. Thanks. 
EDIT: Oh yeah, and I forgot to mention that the pictures will be in color if that gives anyone any more ideas.