Sex dreams, all the time. Flying dreams or dreams with supernatural powers (shooting lighting ala the Emperor). Related to that and ones I hate are dreams where I know that I used to be able to do that, but can’t anymore.
I don’t have the school dreams, but I sometimes dream I am a professional cellist. At the performance, I don’t have my music, or I can’t read it, or the bow disintegrates in my hands or the other musicians are playing a different piece. I do not now, nor have I ever played the cello. It’s super stressful.
Maybe sort of related to dreams in the poll –
Trying to run (either toward something urgent, or away from something urgent) but my legs and feet don’t seem to work right, as if they weighed 500 pounds (seems similar to the trying to fight one)
and
Trying to make a phone call, either to 911 or to another person based on an immediate, pressing need, and the phone doesn’t work for crazy reasons (seems similar to the lights not working). (ETA I see Procrustus has this one, too)
Also school dreams (many years after the fact) where I’m suddenly expected to take an exam but realized I never went to class, that sort of thing.
“Lights not working” is how I know I’m dreaming. I flip the switch, the light stays the same (dim but not off), I think - Oh, I’m dreaming.
I get the “sex with a platonic friend” one every so often. I wake up from those, and think, “Really? Her? Never would have considered…hmmm…mmmmaybe…” 
I, too, have the “tooth breaks / falls out” one semi-regularly.
I often dream of people who have passed away and it’s actually comforting to see them there. Strangely I rarely dream about people I know and when I do it seems almost peculiar and I wonder if something is going to happen to them.
The people I dream of having sex with are either an homogenization of women I know (friends) or total strangers. In my dreams I see myself with a someone like a friend of mine called Anna, but in my dream she has tits and is more curvaceous; so I know it’s not really her as Anna is flat chested and straight as a board.
I checked many of the options. Most of the dreams I remember are stressful. I need to fight but I can’t move/don’t have the necessary strength. I need to get somewhere/do something and everything gets in my way. I get lost and/or sent on senseless side-quests. I’m suddenly back in school and nothing is going my way.
Most of these happen when I’m stressed in the waking world, so I’ve never bothered to study them too much. The terrible thing is that most of my sex dreams also get derailed by this bullshit–unless it’s one of those unattractive/somebody I’d never actually sleep with scenarios, then nothing stops me and that’s in my head forever.
I hate my dreams, most of the time. 
The one I have all the time is “back in school.” More often than not, I have no idea what my class schedule is, and I haven’t been to class for the bulk of the term. I think it’s just the sheer habituation of having been in that place for so long coming back to haunt my aging brain.
ETA: Looks like I’m not the only one!
Usually the light switch dream signifies that I’m at the mercy of some ethereal evil being.
You have lots of company, in fact. In the previous survey I linked, the most common nightmare on the Dope was “unprepared for exam” and the ninth most common was “back to school”.
I’ve never had either, as far as I know. I don’t seem to get any of the standard set of anxiety dreams (unprepared for event, inappropriately dressed in public, teeth falling out/crumbling, and such). The closest I get is trying to find someone or something in a maze, which may be a sort of variant on the “can’t move/get anywhere” type of dream.
I have this one all the time, and it is unbelievably frustrating. Usually, I misdial, and then I hang up to get a dial tone to start again, but I never seem to be able to hang up long enough to actually get that dial tone.
I checked the box about talking/interacting with dead people as I dream about my mother a lot. Most of the time she’s just there, but in a couple I remember being so angry with her in my dream because she died.
I also checked the box about having sex with unattractive people, but it’s a fine line. I’ve had sex dreams about both Jackie Chan (more than once ?! :o) and Al Swearengen (not Ian McShane, but the character). I don’t consider either of those people attractive, so, box checked.
I’ve never had the “teeth crumbling,” but DH has that one a lot.
I have two separate school dreams: 1) I have to go back to high school as an adult; 2) I’m in college (not going back, just a regular student) and I can’t find a classroom. I keep meaning to ask someone, and then somehow, it’s final exam day, and I never did find the classroom.
I got “showed up to school in PJs in elementary school” all the time.
I have had that, but not frequently.
Papergirls, too, and I never once forgot, or was even late, except once when it was the paper’s fault. When I have this dream, I always “wake up in the morning,” (the dream morning) and forgot to deliver the papers the day before, or something totally unforgivable-- not like I’m sitting down to dinner, and the papers are just a couple of hours late (I had an afternoon route-- I imagine people who had a morning route probably dream they are sitting in school when they suddenly realize…).
Also, and I assume only Jews get this, but there’s probably something similar everyone gets: it’s your bar/bat mitzvah, and you have completely forgotten to study. You don’t even know what your haftarah and maftir are, let alone how to sing them, and don’t even know what your Torah portion is, let alone have written a drash (like a homily or short sermon) about it. It’s a little like the one actors supposedly get, where it’s opening night of a play they have never rehearsed.
You forgot about “hero in adventure movie, being chased by bad guys. Lots of Parkour & hanging from ledges involved.”
There’s a recurring dream I have, that I thought I was the only one who had it, but I’ve found out that other Dopers have it too - where I’m in school (usually university) and going to take the final exam for a course, but haven’t studied (in some cases, haven’t been attending lectures), so I have to cram for it.
A recurring dream that’s specific to me: I’m at a campfire and I’ve forgotten to bring the marshmallows.
Yup. They fall out, I stuff them back in and then wonder at the fact that this seems to work. For a while.
Yup. Or college.
Me too. I must be really uptight that even in an embarrassment dream, I’m still wearing my tighty whiteys.
Don’t even know my schedule, but manage to find a few classes, only to realize I’m WAY behind, having missed so many classes since I don’t know when or where they are. And of course, unprepared for the final. Oh wait, that’s not a dream, it’s a memory.
How about lucid dreams (where you’re aware that you’re dreaming)? I love those, they’re so crystal-clear. One time I realized I was dreaming, so I should be able to fly! I leapt into the air …
… and fell to the ground. Repeatedly. Oh sigh.
How about the sci-fi genocidal sympathy dreams. Am I the only one? Example: I have to pull the lever that will kill ALL of the enemy alien race. It’s the only way to save humanity. Yet I am dreadfully sad at the prospect of killing so many innocents, along with the warriors. What else can I do? Emotions run strong, worse than a Disney movie!
Do you dream original music? I think I do. But, I might just be dreaming that part.
Oddly enough, I had both morning and evening routes but the only one that gives me nightmares is missing the morning one. A similar one that I have is having to substitute for a friend’s route only to realize that I have no idea which houses to throw.
I also get one that’s a bit like option 1, but it’s my eyes, not fists. (in my dream)I need to look at something important, but can’t seem to lift my eyelids more than a tiny crack.
I’ve had a few flying dreams,not recently, though I remember the last one vividly and that was years ago. I rarely remember dreams past a few minutes of waking.
I often fall asleep with a TV or radio on, this will influence dreams too.
Me too - if they’re complex or detailed. I sometimes have dreams where I invented something incredible and for a while, I was frustrated by the fact that these incredible ideas fled from my mind soon after waking.
So I put a pen and pad by the bed and the next time I woke up with a fantastic idea, I wrote it down straight away.
When I looked at it later (after waking up fully in the shower) it was complete bollocks - it was English words, but just in an incoherent jumble - proper Shoehorn Butterhorse stuff.