Too Juul for school

On Tuesday, the U.S. Food and Drug Administration sent warning letters to 13 companies that appear to market their vaping products directly to kids. E-cigarettes are a gangbuster business but one device, the sleekly-designed Juul, has really captured the attention of underage teens. Vox’s Julia Belluz explains the hype, and what most teens don’t know about the Juul.