The first time it happens, I'm sort of a bitch about it - I get over to their row and continue lecturing - but I talk louder and louder, until they wake up. If it takes yelling, so be it. By this time, someone next to them usually nudges them. When they wake up, I announce to the class, "...and so that's just about everything you'll need to know for the exam."

Any times after that and I just announce, "this is college, there is no naptime. If you can't stay awake, go home." I have no idea if either of these tactics work, though. I mean, people still fall asleep sometimes.
 

I ball up a piece of paper and throw it at them. When they wake, I say, "You don't have to be here." And I move on.
 

I don't recall its happening back when I taught; then again, there was so much group activity that it would have been hard for it to, most of the time.

Having said that, my first reactions would be to either ignore the student (if they weren't bothering anybody); to wake them up and not say anything other than, say, "you fell asleep"; or (if it really bothered me) to wake them up and say "please don't sleep in my class: it really annoys me when students do that."

What are your goals in that situation? That might suggest some courses of action.
 

I typically ignore it, because I've found that doing otherwise is more disruptive. Depending on the student/frequency/whatever, I may say something to the student later. I do, periodically, say things like "[X behavior] is a bad idea around somebody who is grading y'all" to the rest of the class, which also gets the point across.
 

Why do you care if they sleep? If they aren't snoring or drooling on someone, go on with the rest of the people that are there. Why draw attention to it? You think that somehow embarrassing them is going to meet some goal other than your own self satisfaction that you showed someone up? Perhaps YOU really are putting them to sleep; if talking louder or changing the prosody of your speech wakes them up, perhaps you are a monotone. People in this world are too damn sensitive to rudeness, get over it. Oh and no, I am not a student, I am a college professor and I see a student here or there pass out on occasion. Many of them work full-time jobs and are trying to get an education (no, they aren't entitled to special treatment, but I CAN ignore the occasional dozing off) to better their situation (i.e., getting off of the graveyard shifts that help them to fall asleep). So yes, let sleeping dogs lie and be a human about it; you don't know WHY they are falling asleep, so stop making the classic fundamental attribution error.
 

Where did I say anything about how I handle it, Anon? I was asking for opinions. Clearly you - and others - have them. Thanks for sharing them everyone. I appreciate it.
 

While I'd like to say that my lectures are so riveting that this never happens....yeah, right!

Unless the student is snoring at a distracting volume (this actually has happened a few times, and I just have their neighbor tap them awake. Class giggles. We move on.), I wait until the end of class and speak to the offender privately. I often get very entertaining excuses, ranging from "sorry, I'm hungover" all the way up to "sorry, I was in lockup until 6 am."
 

I don't concern myself with the occasional nod off, but I did have a chronic sleeper one semester. He went into a damn-near coma every class. And he sat close to the front and snorted and jerked in his sleep, so the rest of the students were also aware of him. One day, about 1/3 of the way through the semester, I handed him a large coffee and then asked whether he took cream of sugar. He took both. I stirred it in for him. He drank it, thanked me afterward, and came with his own coffee thereafter.