I put the third row seats down and now I can't get them back up. ??

I had a similar situation. The problem was that when folded, the seats rubbed tightly against each other. I had to reach down between the seats, grab one, and really yank at it to get it to come up. Try this: Flip back the curved plastic panels that cover the hinges for the seats. Each seat hinge is a black metal piece attached to the van body with two bolts. (There is a locating pin near each bolt). Loosen the bolts for one of the seats and use a lever (I used a large screwdriver) to reposition/rotate the seat slightly. Tighten the bolts and try moving the seats. The idea is to reposition the seat so that it does not rub (as much) against the other seat or the side of the seat well. It may take several attempts and you may have to fiddle with the other seat as well. Good luck.

Look in your owners manual.... or wait for another Caravan owner to answer. One would think there is a release lever of some type!