I've actually been engaged since April 4, 2008, but my fiance and I were in high school then and are in college now, so I've just started seriously planning. We've been waiting until I graduated to get married.
Anyway, Steven proposed during our senior year of high school. We were on a Spring Break trip to France with our school, and with all of the romantic settings there, I guess that he decided that while we were there would be the perfect time to propose. Apparently he had had the ring since Christmas and practically the whole school knew what he was planning.
It was a complete surprise to me the night he tapped me on the shoulder as I was looking out at the city lights from the top of the Eiffel Tower. I turned around and he got down on one knee and asked me to marry him. Of course I said yes! That's when I noticed our whole group standing around watching, with our teacher video taping the whole thing.