COLUMBUS, Ohio (AP) _ In this classroom, students can't hear a word their professor says, have to juggle notebooks and jellyfish, and must remember to breathe regularly.



Every January, 15 or so Capital University students dive along a small coral reef off the Mexican island of Cozumel, east of the Yucatan Peninsula, to catalog its incredible biodiversity as well as document natural and manmade factors contributing to its demise.



"It is probably the highlight of my career," said Stephanie Petitjean, 27, of Reynoldsburg, a graduate student who has been swimming the waters since 2005.



"Hopefully these corals won't be extinct by the time I do a postdoctoral (research project)."



Petitjean and other students almost lost their unique classroom once already.



In October 2005, Hurricane Wilma slammed Mexico's Caribbean coastline, wiping away the Paraiso Reef and 10 years of research on at-risk species conducted by Philip Whitford, a Capital biology professor.



"God, where is everything?" Whitford recalled thinking the day he returned to the reef in May 2006. "I had expected there to be damage, yes, but not the ocean floor to be leveled."



Colorful heads of coral once the size of minivans were reduced to rubble. Feather duster worms, Christmas tree worms and sea cucumbers flooded the area to feed on the remains.