Sell your notes

If you dont mind sharing your notes with other students its a great way to generate a little extra cash. There are sites out there that you can upload your notes to, along with your price, and then when another student downloads them you get paid.
Sites like Notesale are free for you to list your notes but tend to take a cut of your profit in order to handle the marketing etc so that you dont have to go out there and promote your notes yourself.
You will most likely have to upload PDFs but its worth it for the return and you can submit handwritten notes but youre likely to make more money if theyre typed up.