Inside a dimly lit chemistry lab, Calera High School teacher Roshawnda Lassiter sprays a bottle of liquid carbon dioxide on an open flame that turns a vibrant shade of green.

The green flame reflects off the safety goggles worn by students enrolled in Lassiter’s forensic science course. The course, in its first year, equips students with the skills needed to acquire physical evidence in criminal investigations.

On this particular Thursday morning, the class focused on arson investigations.

When Lassiter sprayed an accelerant on the open flame, the students jotted down the name of the accelerant and the color it produced in composition notebooks. The students learned sodium chloride produces a yellow-orange flame while potassium produces a purple flame.

Working forensic scientists often determine the accelerant used in arson fires by the flame’s color, Lassiter said.

Since the start of the course, students have conducted fingerprint analysis and hair and fiber analysis.

Lassiter even re-created a crime scene that served as the students’ final exam. Each student had to retrieve and evaluate DNA evidence and determine whether the blood splatters on the walls were due to a gunshot wound or a stab wound.

Lassiter immediately dispelled students’ initial impressions of forensic science, saying the discipline is nothing like a one-hour episode of “CSI” or “Law and Order.”

“You can’t put fingerprints in a database and get them overnight,” Lassiter said. “It takes weeks, months of tiresome investigation.”

Juanna Nixon, 17, a senior in Lassiter’s class, echoed her teacher’s sentiments.

“Everything on ‘CSI’ is completely fake,” Nixon said. “We even had to write a paper about ‘CSI’ versus real forensic science.”

Nixon said the skills she learned in the course can be applied outside the chemistry lab.

“I’ve learned to pay more attention to detail,” she said, “Details can help you not only in forensics, but in life.”