I've used this scale to great effect in my courses for the last few years, but this is first time I am sharing it publicly.
The Zombie Scale of Classroom Participation
4 points = Congratulations! You are a healthy adult human being! And as a responsible adult, you have prepared and are now making quality in-class contributions.
3 points = Hmm. You may have prepared, but your contributions are just OK and don't demonstrate any deep understanding of the material. Perhaps you are just having an off day, OR (!) perhaps you have been bitten and now have the zombie plague! It's hard to say . . .
2 points = It's fairly clear you've been bitten now. You have the creeping zombie crud. Most times, you sit silently, becoming gray and developing the zombie shake. Sometimes you may talk in class, but what you say is off topic, displays no sense that you read the material, or is pure BS. (Of course, I mean BS solely in the technical sense. See Frankfurt, "On Bullshit" .) Every now and then you emit strange, small sounds, somewhere between a wheeze and a snore.
1 points = No signs of human life remain. Your body may be here, but your mind isn't. If any thought is present, it is for checking your cell phone.
0 points = Unexcused Absence. You have become so zombified you are not even here. In all likelihood, you are feasting on someone's liver in the cafeteria.