I have the exam one too! Quite a regular one, like you Jackdaw, I've done all my studying but the location can range from school to university to my postgrad! I'm also always very relieved when I wake up as it's quite distressing.
I studied languages for a while and that is an even more distressing one as it's even more insurmountable thinking I realise I just can't even speak enough of the language to have any chance at even revising.
I used to have a very regular one when I was trying to get away from something horrible, usually trying to get me, and I just couldn't get away until right at the end when I thought I had escaped then whatever it is rears up behind me, then I usually wake up, not nice dreams.
There are quite a few dream diaries on the internet you can search for various things on. Likely others will have had similar dreams.