SAUGUS – The faces of Wednesday night’s students at the Saugus Civilian Police Academy lit up when the police department’s two dogs were brought in for show-and-tell.”I love dogs,” Susan Kreis of Saugus said.However cute, the K-9s are used in the most high-risk police scenarios, officers said.”Being a K-9 officer is one of the most dangerous jobs on the police force,” K-9 Sgt. Tony Lopresti said. “You’re always going after someone who’s armed and dangerous.”Lopresti and Sgt. Tim Fawcett are the two K-9 officers of the police department. The sergeants work regular shifts and bring the dogs home with them, but are often called back to work when the well-trained dogs are needed.Those situations include searching for drugs, weapons and ammunition or helping to apprehend a suspect in an especially volatile circumstance.It costs the department about $10,000 total to purchase a dog and put it through a rigorous 14-week training program, often taught by the Boston or MBTA Transit police departments.”They live with us but they’re technically owned by the town,” said Lopresti, adding that not all police K-9s are social with humans.Lopresti and Fawcett demonstrated for the class how a police dog would bite onto a suspect’s arm while wearing large plastic sleeves around their own arms for protection.The sergeants showed a video of how the dogs, both of which are German Shepherds, are trained to jump over 6-foot fences as well as sniff out drugs.”Once they get something in their heads, they’re going to retain it,” Lopresti said.Before class began, the officers hid a bag of marijuana inside the classroom at the Saugus police station. Upon the sergeant’s commands, Fawcett’s dog “Bennie” went wild before sniffing out the bag of pot that was hidden in a plastic container.”Here’s what was in there,” Lopresti said while holding the weed.He said Bennie is often motivated by toys while his dog, Gaston, is motivated by treats.Fawcett said he knew Bennie was motioning that drugs were inside the container due to the pooch’s head movements.”He gave a quick head jerk,” Fawcett said.The officers say having the dogs is a big help especially when an armed suspect is involved.”It takes a lot of stress off of us when the dog is 35 feet ahead of us,” Sgt. David Gecoy said.It’s mandatory for trainers to fire blank gunshots at the dogs and for the dogs not to flinch in order to work for the police.”They fire blank rounds at him so they’re not afraid of gunshots,” Fawcett said, adding that if the dog flinches they’re not accepted by police.Bennie, who is 9 years old, is starting to age but appears to be in good shape.”It all depends on health,” Lopresti said. “If they’re 10 and they’re still working, you’ve got a great dog.”Sherri Lopez of Saugus says the six-week course showing citizens the inner workings of the police department has been a blast.When asked if it was fun she answered, “Oh God, yeah.”Both she and Kreis said their favorite part of the course was doing a police ride-along, in which they got to accompany a police officer on his shift.”We got to assist in a pull over,” Lopez said. “That was the highlight of the course.”For the housewives we are, it was a big thing,” Kreis said with a laugh.