Princesses, pigs and jack-o’-lanterns in strollers haunted the ISU campus Monday night as children from the Ames community roamed dorm halls and campus buildings for a safe Halloween celebration.

Six engineering organizations hosted a Halloween event in the Black Engineering Building, as students dressed up to play “monster musical chairs” and handed out refreshments to the kids. Shrieks of terror and delight rang from a haunted house, and a boy dwarfed in a pig costume ran down the hall proudly holding his prize, a bag of Skittles.

The engineering students said the event is a safe alternative to the dark streets and traffic associated with traditional trick-or-treating.

“It’s a safe Halloween thing,” said American Society of Materials member Jennet Kramer, freshman in materials engineering. “You don’t have to worry about them getting bad things from bad people.”

The service event helps unite the university and the community in keeping Halloween safe, said Sydney Kokjohn, member of the Society of Women Engineers.

“It gets the rest of the community involved in the college,” said Kokjohn, sophomore in chemical engineering, as she and Melissa Lamkin, sophomore in mechanical engineering, served cookies to two members from the Blues Clues cast.

After claiming her prize from a round of musical chairs, Marta Pate, 5, said her favorite part of Halloween is dressing up and eating candy.

“I like Barbie princesses,” she said, as the theme from Ghostbusters played in the background. “I was a princess last year too, but I had a different costume.”

Residents of Oak-Elm Hall welcomed trick-or-treaters to their rooms with costumes and plates of candy.

Julie Bruxvoort, resident of Merchant floor in Elm Hall, said the supervised atmosphere grants parents peace of mind and allows ISU students and children from the community the opportunity to interact.

“It’s a safer environment here than having [the children] walking around outside in the darkness,” said Bruxvoort, sophomore in pre-advertising.

Greek houses along Ash Avenue also will welcome trick-or-treaters from 6:30 to 8 tonight.