By COLLIN BINKLEY, Associated Press

BOSTON (AP) - Schools and health officials across the U.S. are struggling to curb what they say is an epidemic of underage vaping.

Officials say teens and children are getting easy access to e-cigarettes and other vaping devices, which heat liquid into an inhalable vapor that often contains nicotine.

Vaping is illegal under the age of 18 in many states, but students say they can buy them online or from older friends.

Federal health officials say they're cracking down on underage sales and also exploring whether certain features of the popular brand Juul appeal to young people.

Schools have responded with educational campaigns, and some now deal automatic suspensions for vaping.

The latest federal data showed a dip in teen vaping in 2016 after years of growth. Updated numbers are expected in June.

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