"We need more affordable housing and wages that can allow people to live in that housing," she said.

Community activists said they were surprised and heartened to see Harvard students so passionate about issues of homelessness and housing.

The handful of homeless people attending the sleep-out said it was particularly poignant for them to be invited to an action just outside the gates of Harvard Yard.

"You'd think Harvard would be a bastion of science, computers, conservatism and capitalism," said a homeless activist and housing advocate who said he goes by the name "Outrageous Raging Love." "This is a sacrifice for students to leave their warm dorms for a night. Maybe activism isn't dead after all."

Love, who held a brightly-colored sign reading "People for the Ethical Treatment of the Homeless," said he planned to spend the night outside the Science Center if he could find his way into one of the tents.

""This is a very spiritual experience," Love said, looking around at the students setting up camp for the night. "I've asked myself whether a homeless person would be welcome in this Yard. The answer tonight is a resounding 'yes.' That's a warm feeling."