Using tweezers to pick up bits of string and cotton swabs to collect samples of a mysterious red liquid, the seventh- and eighth-graders try to figure out what happened to Felix Navidad.

Was he killed by jealous friends during a party? There is no corpse at the crime scene, so was there even a crime? The 19 students will find out by analyzing fingerprints, fluids and other physical evidence during a weeklong summer camp at the American Museum of Science and Energy.

They are among the hundreds of students attending camps all over the nation this summer to learn more about forensic science.

Inspired by the rising popularity of the "CSI: Crime Scene Investigation" television show and its spinoffs, universities, museums and other organizations are offering workshops and classes to teach children about the science of sleuthing.

Alyssa McCartt, a promising seventh-grader at the camp, said she enjoys the CSI shows and wants to make forensic science her career.

"I watch it while eating dinner, and I don't get sick," she said.

The National Science Teachers Association and the American Academy of Forensic Sciences have reported a surge in interest among students, and many schools already include some aspects of forensics in the science curriculum during the school year.

The camps aim first to get youngsters interested in science, not necessarily to encourage them to become investigators.

"They are intrigued by that whodunit type of experience, and we're thrilled it provides a good avenue for students to learn science and learn how science is used in the everyday world," said Cindy Workosky, spokeswoman for the teachers association based in Arlington, Va.

Students at "CSI: AMSE" in Oak Ridge studied a mock crime scene surrounded by yellow caution tape and strewn with empty soda cans, sunglasses, an alarm clock, a half-full ice tray and footprints.

Then they put on latex gloves and collected the evidence, carefully placing each item in a separate plastic bag and labeling it.

Many camps are geared toward middle and high school students. But a CSI camp in Knoxville last year for ages 9 to 11 was so popular that the organization decided to try a three-day camp for ages 6 to 8 this year.

Instead of investigating a mock crime, 15 squirming students learned about hair, teeth and lip impressions during the Dynamic Detectives camp offered by the East Tennessee Discovery Center.

Studying lips presented a challenge to the boys, who yelled "Yewww!" when the teacher said they had to put on lipstick and blot their lips on a piece of white paper.

Even young students such as 8-year-old Sarah Wharton, who said she learned about detectives by watching "Scooby-Doo" cartoons, understand some of the concepts in forensics.

While discussing hair samples, Wharton proclaimed: "You can scan the hair and figure out whose hair it is."

Some camps try to offer students a more realistic glimpse at investigations by tapping into law enforcement sources. A camp set for August by the South Burlington, Vt., recreation and police departments will include field trips to a laboratory. An overnight camp at Waynesburg College in Pennsylvania next month for high schoolers is to have a demonstration by a bomb and arson unit of the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Thanks to the growing interest in forensics, there are plenty of lesson materials already available for teachers.

The teachers association, the American Academy of Forensic Sciences and Court TV developed a curriculum called Forensics in the Classroom that teachers can download free from the Internet.

The academy has held conferences for middle and high school teachers since 2002 to show them how to present forensic techniques in an accurate way, since the TV portrayal is not always the way it is in the real world.

The mystery of Felix Navidad taught at the Oak Ridge camp is based on a series of lesson plans called Mystery Festival from GEMS, or Great Explorations in Math and Science, at the University of California at Berkeley.

GEMS published its first teaching units in 1994.

"We were actually ahead of that curve," GEMS Associate Director Lincoln Bergman said about the influence of CSI. "Those shows tend to have an emphasis on very highly technical forensic science. In the classroom with simpler hands-on equipment, you can still do wonderful things, but it's not like having an X-ray or something like that."

Still, some camp organizers create their own scenarios, making sure to keep the activities fun and lighthearted.

Girls attending the Young Women's Summer Science Camp at Washington State University Spokane CityLab pore over a crime scene, study fake DNA material and then put on a mock trial using their evidence.

"They do all of that," program coordinator Glynis Hull said, "and then we have pizza."

Karen Bradley, an instructor in a Dynamic Detectives class, helps 6-year-old McKenna Sibold take her own fingerprint during a summer camp held at the Candy Factory in Knoxville, Tenn.