Quincy (WGEM) -- Is your teen Juuling? A Juul is a very small e-cigarette that's popular with teens because it's the size of a flash drive, and easy to conceal at home and at school.
A growing number of teens are hitting the Juul and many parents likely have no idea.
"In the bathroom," Ft. Madison junior Aniah Ross said.
The small sizes often allows teens to hide them in plain sight.
"Sometimes in class when the teacher is not looking," Ft. Madison senior Gage Lange said.
Juuling is skyrocketing among teens. More than one-third of high school seniors vape, according to a National Institute on Drug Abuse study released just last month.
Fort Madison High school students say their classmates are no exception.
"Probably 20 to 30 percent," Ross said.
"40 to 50 percent," Lange said.
It's not just high schoolers using. E-cigarette use is up significantly among younger kids, too.
"I've known people that started using it when they were in eighth grade and they are freshman now," Lange said.
Northeast Missouri teen Brittany Hunter started vaping three years ago when she was 15.
"I was never been attracted to actual cigarettes. I don't like the way they smell and all the side effects of them," Hunger explained
Ft. Madison High School Principal Greg Smith says the district first became aware of Juuling last year.
"When it popped up on our radar the kids that we caught first were NHS, fabulous straight 'A', good families," Smith said.
While the school district is now more aware, many parents likely have no idea their kids are Juuling.
"I think a lot of them are hiding them from their parents," Ross said.
Smith says a Juul is hard to detect even in the classroom, but when it is it's confiscated, the student is suspended, and parents are notified,
"We monitor and we walk the halls constantly and stop into restrooms during the day and just spot check, but it's very difficult to catch them," Smith explained.
Part of what makes them so discreet is what also makes them so appealing to young users.
"Most of the people I know have weird flavors like strawberry watermelon and they are like this is the best," Ross said.
Hunter says the fruity flavors and smoke tricks her boyfriend did are part of what attracted her to vaping.
"He started doing all the smoke tricks and I thought they were really cool, so I was trying to do them and ever since then I just fell in love with vaping," Hunter said.
Medical experts warn the brightly colored packaging and fruity flavored juices shouldn't distract from the real danger.
"The way it's marketed may make it sound like it's benign and it's not," Quincy Medical Group's Dr. Adam Reyburn said.
According to the U.S. surgeon general, most e-cigarettes, including the Juul bran which accounts for 75% of the market, contains nicotine a highly addictive drug.
"Mood disorders, depression, potential cognitive development as well, decision making," Reyburn said. "The effects on the brain and brain function and brain development are larger and more significant than if you are an adult and your brain is already developed."
Hunter says she does not believe she's addicted to it.
"I can easily forget my vape at home and be fine all day with no mood swings," Hunter said.
Even with the health risks, teens are still picking up the habit.
"Sometimes it's just to fit in with the older kids," Lange said. "Also, stress relief. School can be pretty stressful now. We get a lot of tests and a lot of your future is just decided by school."
"Stress, anxiety, but I think it's mainly to be cool," Ross said.
A trend that's putting teens' health in danger.
- National Institute on Drug Abuse: What are electronic cigarettes?
- American Lung Association: E-Cigarettes
E-Cigarettes and Young People: