I must first state that I'm not a parent, but I have taught high school and middle school. My current work focuses on providing tweens and teens (and the educators that serve them) with healthy hands-on learning experiences and promote whole-person wellness.
That said, I would like to share a quick personal story. A few years ago, my husband (and business partner) and I were hosting my niece's 13 year old birthday party at our house. Being the big kid that he is, my husband broke out the tools that we use in our workshops - skill toys such as spinning plates, flower sticks, and other juggling like objects that are "powered" by physical skill and practice. The toys were a huge hit and it wasn't until about 45 minutes later that the first phone came out. And it was to take a picture of one of the girls with a couple of plates spinning . It was that night that we came up with the line - "Hands-on and thumbs free!"
From our teaching experience, research, and many anecdotal stories such as this, I have the following suggestions for parents of tweens and teens: