What is worse than losing your laptop? Losing your 20 page final paper that is due tomorrow and isn't backed up anywhere.
Back up your work to a USB flash drive. These are available at the Bay Tree Bookstore and in the learning supplies vending machine on the second floor of McHenry Library. Obviously, don't leave this connected to the laptop when you are away from it.
Back up your work to the cloud. Use your Google Drive.
Back up your work to your campus network share.
Email a copy of your work to yourself.