If you want to incite your teacher's sympathy and your excuse is less-than tear-inducing, it might be appropriate to tell a creative rendition of the truth. Been spending way too much time on Facebook? Let's say you have had technical problems and your WiFi gave out. Did you just break up with your significant other and haven't had the time to write anything? Let's say it was a family emergency. It may not work, but your chances often depend on how well you can explain the situation.