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Mary Hanson is a high school science teacher. She is also a reserve officer in her local police department. Student misbehavior, she likes to say, is rarely a problem in her class.

A more serious challenge for her and for teachers across the country is how to get students interested in the subject and help them make sense of important content. In recent years, she has found that one course in particular鈥攆orensic science鈥攊s well suited to that mission.

Over the past decade, forensic science has carved out a sizable niche in the science curriculum, not only in Ms. Hanson鈥檚 school but in districts nationwide. Once found almost exclusively on college campuses, increasingly sophisticated forensics lessons鈥攖ypically focused on crime-solving techniques鈥攈ave become entrenched in many high schools and even some middle schools as electives or sections of core science classes.

Figures from the speak to the improving status of forensics. In the past three years, the number of forensics-themed topics at NSTA conferences has climbed from 61 to 98, said Francis Eberle, the executive director of the 58,000-member organization.

Many trace the popularity of forensics to a well-known source: the television series 鈥淐SI鈥� and its spinoffs, as well as the proliferation of true-crime shows.

The link between those shows and student learning is unclear. A report released this year by the congressionally chartered National Research Council found modest evidence that shows like 鈥淐SI鈥� have a positive effect on students鈥� view of science as a career鈥攑articularly females, when they see women shown as scientific contributors. (鈥淚nformal Experiences Can Go A Long Way in Teaching Science,鈥� Jan. 28, 2009.)

Hip Technique

For educators like Ms. Hanson, who teaches a forensics elective at Arlington High School, in St. Paul, Minn., the appeal to students is clear. The nitty-gritty of forensics, whether it involves studying a shoe print or fibers from a crime scene, she noted, excites students in a way that much of traditional science often does not.

Ms. Hanson fully acknowledges that 鈥淐SI鈥� has led students to her class. But once they arrive, she emphasizes that forensic techniques鈥攆ingerprinting, handwriting analysis, or photogrammetry (making measurements from photos, such as a suspect鈥檚 height in a surveillance video)鈥攁re more precise and laborious than they appear on TV.

鈥淚t鈥檚 a good Hollywood drama,鈥� Ms. Hanson said of the show. 鈥淚t gets people interested, and I can teach the science. ... But I tell them, it鈥檚 going to take us four days to do this [work], not 45 minutes like they do.鈥�

Ms. Hanson draws from work, and from the academic content in other science classes she teaches, in her forensics class. Students use geometry, for instance, to study one of the grimmer aspects of a crime scene: blood spatter.

Other activities combine scientific and legal topics. Ms. Hanson recently dimmed the lights in her room and held up differently colored papers and light bulbs, asking students to record the colors they saw. The exercise covers physics, but also investigative issues: Most students misidentified 50 percent of the colors, she noted, a reminder of the difficulty of judging eyewitnesses鈥� claims, particularly in poor lighting conditions.

One participating student was Emily L. Patterson, 16. Ms. Patterson was drawn to the class because she likes different 鈥淐SI鈥� shows,which she often watches when she gets home from school.

鈥淚 liked how it鈥檚 hand-on,鈥� the 10th grader said of the forensics course. Compared with other science, forensics 鈥渟eems easy to me,鈥� she said. 鈥淚t鈥檚 actually getting to do what you see on the show.鈥�

But Ms. Hanson is now a more discerning viewer. When certain forensics aren鈥檛 depicted accurately on CSI鈥攖he teen recalls a fingerprinting technique鈥攕he says she knows it.

Tracing the exact arc of forensic science鈥檚 popularity in K-12 schools is difficult. But there is little doubt the original show, 鈥淐SI: Crime Scene Investigation,鈥� which debuted on CBS in 2000, pushed the phenomenon. The show, which quickly became one of the most popular on television, chronicled the work of Gil Grissom, a fictional forensic scientist, and other Las Vegas Police Department investigators. The original drama is in its 10th season; other 鈥淐SI鈥� shows have been created since then, set in Miami and New York City.

In a 2004 NSTA membership survey, 77 percent of middle and high school teachers said that 鈥渇orensic investigations鈥� were taught in some form in their schools, and roughly the same proportion credited TV forensics shows with sparking students鈥� interest in the subject.

The use of forensics in science, Mr. Eberle noted, is broader than the popular understanding of 鈥渇orensic science,鈥� often defined as the application of science to the law. In general, forensics can refer to the process of investigating evidence in any number of scientific areas, from studying glacial ice sheets to the behavior of wildlife.

Even when shows like 鈥淐SI鈥� aren鈥檛 scientifically precise, their positive impact comes in their presentation of scientist-cops doing interesting work, Mr. Eberle said鈥攁n image far removed from the stereotype of the research scientist toiling in obscurity.

鈥淚t shows adults using scientific techniques that are cool or hip,鈥� Mr. Eberle said.

The idea that 鈥淐SI鈥� can stir students鈥� science passion makes Richard Catalani, a producer and technical adviser for the show, 鈥渉ugely proud,鈥� he said in an interview. Mr. Catalani, a former crime-scene investigator with the Los Angeles County Sheriff鈥檚 Department, says he understands students鈥� frustrations with traditional science. His record in school was mediocre 鈥渁t best,鈥� he admits.

鈥淚 decided I wasn鈥檛 ever going to be an A student,鈥� said Mr. Catalani, but he came to love the 鈥減ractical application鈥� of science.

How Far to Go?

Critics of the 鈥淐SI鈥� shows say they oversimplify the science and create public misconceptions, such as some jurors鈥� mistaken belief that DNA is available in every criminal case.

While he understands that criticism, Mr. Catalani says he believes 鈥済ood far outweighs the bad,鈥� as far as CSI presenting forensics to the public and students. The show has to 鈥渃heat the time factor,鈥� he said, to tell a story. No one can analyze DNA in 45 minutes, he conceded: 鈥淚鈥檝e been on a single crime scene for 24 hours.鈥�

Crime-science forensics is often gruesome work, and teachers and publishers sometimes struggle to decide what content to cover. The education division of Pearson, a publisher in Upper Saddle River, N.J., has teams of teachers and forensics experts review textbooks鈥� content and age-appropriateness, said Brent McKenzie, the vice president of product management and marketing for K-8 science. Pearson published a college forensic-science text in 1977, which was later adapted into a high school version. A middle school supplementary text was unveiled two years ago.

An early draft of the middle school textbook, describing how a gun barrel leaves an impression on a bullet, included an image in which readers appeared to be looking down the barrel of a firearm, Mr. McKenzie recalled. Reviewers thought it was too graphic, he said, so the image was turned into a more detailed diagram showing a gun鈥檚 inner mechanics.

Pearson officials are confident in their texts鈥� authenticity: The high school book鈥檚 primary author is Richard Saferstein, former chief forensic scientist at the New Jersey State Policy Laboratory.

Tanya Sterba, a science teacher who leads a forensics elective at Cheshire High School, in Connecticut, has sought out authoritative sources on her own: She obtained crime-scene processing forms and other documents from nearby police agencies. She uses the documents to guide students through the lengthy process of analyzing a crime scene鈥攑hotographing and sketching the area, monitoring who came and went, recording lab results.

It can be mundane stuff. But her students haven鈥檛 complained.

鈥淵ou鈥檙e reaching students who in many ways have been turned off by science, and you鈥檙e re-engaging them,鈥� Ms. Sterba said. At the end of a year researching crime-science forensics, she said, students who had once refused to do homework are wrapping up investigations by asking, 鈥淚s there anything else you need me to do?鈥�