This class project is really simple, and you can work on it while taking the course! Take one image from the web or your phone (or use one of the ones I've provided under the class project tab), choose something in it to isolate, and give it a new background!
Here are some ideas:
A picture of yourself: Never been to Paris? Cut yourself out of a selfie and put the eiffel tower in the background.
Your favorite product: Snap a quick photo of your favorite product, isolate it, and use it to create a fake advertisement (great for portfolios!)
A collage: If you really want to go above and beyond, cut out a bunch of stuff and arrange them in a stylish collage.