CHICAGO–For Satit Koonopakarn, the gold dagger and book of chants were the first signs of trouble. 

His freshman roommate at the University of Illinois at Chicago pulled out the items on move-in day, explaining that he was a Wiccan and liked to practice witchcraft. Months later, Koonopakarn said, he awoke during the night to find the roommate standing over his bed casting a spell.

“I was lying there thinking, ‘Please God, don’t let anything bad happen to me,'” Koonopakarn said with a chuckle.

Like most colleges with residence halls, U of I-Chicago makes an effort to pair first-year roommates who are compatible, often taking into consideration personality assessments and lifestyle questionnaires, among other factors. But some matches still result in disaster.

To minimize the horror stories, a small but growing number of schools are inserting online technology into the equation. They are setting up their own social networking sites, instructing students to create a profile and select a roommate for themselves _ like Match.com for dorms.

Assigned roommates have already seized on Facebook and Myspace as a way to learn more about each other. Colleges field complaints from students, and their parents, seeking roommate changes even before the school year begins. Loyola University recently heard from the mother of a student who pulled up a photo of her roommate’s house on Google Maps and deemed it too shabby.

While some schools are now trying to use the technology to their advantage, other schools are pushing forward with traditional matchmaking, insisting students need to branch out of their comfort zones and experience diversity.

For the nearly 2.8 million freshmen heading off to college _ one of the highest numbers in history _ the roommate relationship may have the single greatest impact on their college experience, studies show. Students dissatisfied with their roommates are more likely to feel negative about college and suffer lower grade-point averages and retention rates.

“It can make or break a student,” said Mike Schultz, director of university housing at Southern Illinois University-Edwardsville, who serves as president of the Association of College and University Housing Officers International.

“Some students will leave a university if they have a poor experience. I’ve also seen marginal students with great student relationships succeed with the extra support.”

DePaul University had used a lifestyle questionnaire when matching freshmen roommates, striving to pair early birds with other early birds, self-confessed slobs with equally messy classmates, and smokers with those who shared the habit.

But eight years ago, the university scaled back the criteria, asking only which residence hall and type of room the student preferred, said Rick Moreci, director of housing services.

“When we asked more questions, the students were even more upset when we made a bad match,” Moreci explained. “With less factors at play, students don’t have as much of a basis to complain.”

Starting next year, the college will take its hands-off approach further, allowing freshmen to select their roommate through an online networking site created by a company called Lifetopia.

Lifetopia-designed sites allow students to post photos and details about their background and interests, then shop around for compatible classmates.

Within the past several years, the company has signed contracts with more than a dozen colleges, including San Francisco State University.

The California school offers the Lifetopia network to students selecting roommates for off-campus housing and a similar in-house online networking program for those living in residence halls on campus.

“We’ve found that there’s less conflict when the roommates select each other,” said Philippe Cumia, the school’s associate director for administrative services. “Giving them a choice gives them a greater stake in the relationship and making it work.”

Even at schools without Lifetopia, some students are selecting their roommates through Facebook and MySpace.

This summer, Danielle Sterczek, 18, of Palatine, Ill., and Krysten Karns, 18, of Aledo, Ill., received random roommate assignments from the University of Illinois Urbana-Champaign. But once they discovered each other’s profiles days later on a group of incoming freshmen formed on Facebook, they successfully sought a swap.

Based on their profiles and online chats, it appeared they had a lot in common _ including playing high school sports.

As long as everyone, including the original roommates, was in agreement, the college approved.

But many colleges insist that by selecting roommates online, freshmen miss out on the valuable learning experience that comes from living with people of different backgrounds.

“The more diverse the mix, the more interesting the conversation, thoughts and experiences that will emerge,” said Katie Callow-Wright, director of undergraduate housing at the University of Chicago.

• Megan Twohey