STATE COLLEGE, Pa. -- The dummy never had a chance. It was stabbed in the chest by a burglar inside the home.
Days later, a horde of official-looking people surrounded the body, which was lying face down on the floor. They scribbled notes on legal pads, looked for fingerprints, and discussed how to take samples from the blood around the body.
''You guys have to remember to look at all the alternatives," a forensic scientist, Robert Shaler, said suddenly over a loudspeaker system, startling the investigators. ''Sorry, I didn't mean to scare you."
This is Shaler's crime scene lab, where, twice a week, the director of Pennsylvania State University's forensic science program turns the old home in the middle of the sprawling campus into a three-story classroom to teach students about his work.
''It's great," Shaler said recently from the basement of the lab housed in Spruce Cottage. ''I've always thought that this is the way you teach students how you investigate crime scenes. Get them acclimated."
The class started this semester under Shaler's direction, and the cottage is home to one of just two such classrooms at a university, according to Shaler and Earl Wells, president of the American Society of Crime Lab Directors. The other lab is at West Virginia University.
Most rooms at Spruce Cottage are wired with expensive audio and video equipment so Shaler can observe students from a basement monitoring station that looks more like a security hub at a large office building.
Shaler often wears two headsets at the same time -- each one monitoring a floor of the house. He pipes in over the intercom system to answer questions and give tips, often unsolicited.
''The very first time I heard him, it was like, 'Whoa, where did that come from?' " said Ashley Dart, 19, of Lancaster.
It's a change of scenery for Shaler, who retired last year as the chief forensic biologist at the New York City medical examiner's office. There, he led efforts to identify victims of the Sept. 11 attacks on the World Trade Center.
Now, he trains aspiring forensic scientists who have grown up watching investigative crime dramas on television, such as ''CSI" and ''Law and Order." The shows have boosted enrollment in forensic science classes nationwide.
In Spruce Cottage, like on the TV programs, the crime scene is a star of the show.
Built in 1890, the cottage has been used for everything from a sorority house to headquarters for campus security to a faculty home.
Forensic science took over the house last year, when it was renovated to its current specifications.
At first glance, the house is oddly situated against the backdrop of the modern brick-and-glass buildings towering behind it on campus.
Two recent crime scenes, one on each floor, had been set up by Shaler days earlier. The crime scenes confronted the students as soon as they walked into the front door of the cottage.
Usually, Shaler scripts and tapes a scenario, and then sets up a scene matching the video.
One video, for example, involves Shaler being stabbed in his living room by an intruder. With the cameras off, his ''body" is replaced by a life-sized dummy on the floor; cow's blood, which has been decontaminated, has been strategically placed or smeared around the house as evidence; and ''suspect" footprints are put inside and outside the home.
''It seems pretty realistic to me," Jennifer Skrzypczak, 25, of Erie, said as she measured the room's dimensions with a tape measure. ''But it was a little creepy walking in the first time."
After the students examine the house, they are shown the video of the ''crime."
A schedule outlines future class topics that sound like a TV crime show spinoff: ''Time of Crime: Blood drying time" and ''Ballistics Evidence: GSR" -- or gunshot residue analysis.