One Los Angeles school is working technology into the learning process while avoiding traditional screen-time pitfalls.

Now researchers at the Hong Kong University of Science and Technology have developed a new type of LCD screen that works in a similar fashion. It can hold a static image for years with no power.

And how much they're used. And what they're used for," says Patricia Greenfield, who co-authored that screen-time study we mentioned earlier. She's a professor of psychology at UCLA and has been ...