NEW YORK (AP) — About 1 out of 5 high school students in the U.S. say they vaped marijuana in the past year, and its popularity has been booming faster than nicotine vaping, according to a report released Wednesday.

"The speed at which kids are taking up this behavior is very worrisome," said Dr. Nora Volkow of the National Institute on Drug Abuse, the federal agency that pays for the large annual teen survey.

Electronic cigarettes and other battery-powered vaping devices mostly heat a liquid containing nicotine into a vapor that's inhaled, In recent years, they have been increasingly used to...