He said part of what the classes were studying was the genetics of fingerprints and the uniqueness of DNA.
"They need to learn to filter out hearsay and go back to the facts," Center said.
Each of the three classes was split into teams charged with investigating different parts of the scene.
One team checked shoeprint patterns and compared them with those of the suspects. Another team collected pollen samples and compared those with samples from the suspects.
There was even blood evidence that led to Andrea Murgu's classroom.
"The blood outside was candy," shouted seventh-grader Jose Arce, who backed up his theory with a few facts. "It's sticky, and I know candy."
Students compared some of the evidence using microscopes and collected DNA using gel electrophoresis.
After gathering the pieces of evidence, the teams shared their findings and received the last two pieces of evidence: the DNA and pollen matches. The evidence from the scene matched Suspect 1: history teacher Ray Triggs.
Before those matches were revealed, about half the class thought Murgu was the culprit. A few thought it was Triggs and even fewer pointed fingers at administrative assistant Annette Arora.
When Triggs was revealed as the match to the DNA and pollen, Diego Vidrio shouted: "I win! I win!"
But the work wasn't finished yet. The students still had to compare what they'd found and decide which suspect had the most overwhelming amount of evidence going against him or her.
"They need to pull it all together and come to a conclusion and back it up with facts," Center said.
Though Triggs was starting to look pretty guilty, student Ray Welsher wasn't buying it. He suggested Triggs was framed — he was sticking to his theory that Arora was guilty.
But Center pointed out that while a shoeprint or a can with a fingerprint could be planted, it would be harder to plant the blood.
Shoutouts from the class agreed.
"Where would you get the blood?" a few asked.
The project had at least one hidden bonus — a possible job option.
"We learned how we can make a career out of it," Sarah Javier said. "It's fun to do."
Disclosure: Freelance writer Alicia Lopez's son attends Costa Mesa Middle School and is enrolled in another section of the same course.