A growing number of e-cigarette and vaporizer sellers have started offering college scholarships as a way to get their brands listed on university websites and to get students to write essays about the potential benefits of vaping.

The tactic is taken from a method that was once believed to improve a site's ranking in search results, and it has successfully landed vaping brands on the sites of some of the nation's best-known universities, including Harvard. It also has drawn criticism that the scholarships are a thinly disguised ploy to attract young customers. The scholarships, ranging from $250 to $5,000, mostly involve essay contests that ask students to write about the dangers of tobacco or whether vaping could be a safer alternative. At least one company asks applicants to write about different types of e-cigarettes and which one they recommend. Some seek papers in support of medical marijuana. Over the last two years, the grants have been posted online by e-cigarette retailers and review websites such as Slick Vapes, SmokeTastic and DaVinci Vaporizer. Robert Pagano, owner of the Las Vegas-based review site Vapor Vanity, said he was offering new scholarships of up to $1,500 this year. He acknowledged it's partly a marketing tool, but he also says many in the industry are former smokers and want to help teens avoid tobacco.

The grants have emerged as high schools struggle to rein in booming teen use of the devices, sometimes threatening students with suspensions or installing alarms that can detect the devices' discreet vapor.