Glass rained down last week in the Butler University greenhouse for the second year in a row.

Phil Villani, associate professor of biological sciences and the manager of the greenhouse, said someone tried to walk on the metal grates between the glass window panes sometime during the weekend of Sept. 10.

While the person did not fall though the glass, he or she did break three windows.

Villani said it looked like he or she was trying to write lyrics from the Katy Perry song “Teenage Dream” on the glass.

The university put up signs warning passersby that the greenhouse is made of glass when a freshman fell through after sitting on it last September. That student told police he believed the greenhouse was made of brick.

“Students should know that it’s glass, and the average person knows it’s not a good idea to step on it,” Villani said.

The greenhouse’s Facebook page had a photo of the broken windows along with a caption that read “It happened again, 2011.”

The biological sciences department’s page had the same photo with the caption, “hey…let’s all agree not to try to walk on the greenhouse anymore, k? great, thanks.”

Villani said these incidents are the only times students have damaged the greenhouse in its approximately 30-year history.

He said there is little else the school or department can or should do to ensure it doesn’t happen again.

“You can’t protect against stupidity,” he said. “You can’t put a wall around the greenhouse.”

Villani said the damage will cost at least $500 to fix.  He said that if authorities cannot identify who broke the windows, the cost will fall on the university or the biology department.