They were at the Hotel Montana" in Port-au-Prince when the quake struck.
Eight of the students made it out alive and returned to Florida on Friday.
The search continues for the .
Several of the students recalled their time of terror on "The Early Show Saturday Edition."
Lindsay Doran told co-anchor Chris Wragge it was a "living nightmare." "My first thoughts," she said, "were, 'This isn't real, it's basically a living nightmare.' That night of the earthquake, you just sat there anticipating another aftershock, and if you were going to be OK. And basically I just stood by my friends' side. ... I don't think I could have made it through those next couple days without any of them."
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P.J. Tyska recalls he thinks he "was just in shock, and just didn't even know what was really happening or if that really happened. So, all eight of us got together and, as soon as we did, that was it, all eight of us were together from then forward."
Getting back to the United States was, he said, an "indescribable experience. It was long and tiring. But we made it and we're here, and we can't really describe what we went through. It was difficult."
Nikki Fantauzzi remembered that the eight who escaped were outside, but the others were in the hotel. "We still are hopeful," she said, "that they will be found and that they're OK. That's the only thing we can do, and we're still praying for them."
Tyska added, "This is not going to be a success story until we have our other four students and our two teachers back. And we are all praying that that is a very big possibility."
They ones on the show said they want to go back to Haiti, and idea their families are frowning on.
But one said, "When we got back and knew that we were safe, we were just like -- we need the rest of our group and all the other people out there. So, yeah, (we want to) go. We want to do anything we can. And everyone watching, do anything you can to help."