A student at Milpitas Unified spends around 30 to 150 minutes a day (depending on grade level, instructional objectives, and other learning/personal factors) with a screen.  Here is one person's perspective based on evidence.
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"When I was a kid, my parents had strict television rules: no more than an hour a day, and the content must be educational. This meant a lot of PBS. I did briefly convince my mother that the secret-agent show “MacGyver” was about science, but that boondoggle ended when she watched an episode with me. These restrictions seemed severe at the time, but my parents were just following the orders of the American Academy of Pediatrics (AAP): Children and teens should have no more than..."

Read on @ FiveThirtyEight

Michael Horn provides his insights on innovation from his new book, Blended.
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"When it comes to innovation in education, there is a tension.

Some educators express concern about innovating when children are involved. Innovation implies experimentation and uncertainty. Aren’t “disruptive innovation” or even “breakthrough sustaining innovations” too risky to pursue in schools given that the well-being of children is at stake?

Other educators come at it from the opposite perspective. Believing that current schools aren’t good enough for students, they think avoiding innovation in schools is akin to malpractice.

In our new book, Blended: Using Disruptive Innovation to Improve Schools, Heather Staker and I devote a chapter to sketching out a way to innovate that takes into account the truth in both positions: the need for caution in unpredictable innovations, and the need for innovation to improve how educators serve students."

Read more on edSurge