My wife is a pediatric occupational therapist who works with children in Silicon Valley, including the some of the uberwealthy (Los Altos Hills, Portola Valley ranch wealthy, "would you just come with us on the jet this week" wealthy). She has also worked in pre- and post Katrina New Orleans, college towns, east coast, west coast. tropical islands. She's been around, seen kids at the absolute top and some versions of the very bottom (families living in shipping containers). I'm a physician informaticist. our kids are now 17 and 20. One is going to UCLA, the other is going to run out math at the local community college before he graduates high school.
I generally agree with the others who say if you can solve child-rearing, please let me know, we're going to be rich.
That said, the best advice I can offer is exemplify the adults you wish them to become. To the extent possible, raise children through benign neglect.
That said, screen time is the devil incarnate. You don't want your kids to be the first ones with a phone, or the last, but you should try to be as close as possible to last as you can.
The pediatric in-patient psych beds in California were full a decade ago. Californians are now filling all the psych beds in the neighboring states. It seems to hit young teen girls the worst. If you want a peds psych bed and you live in California, start looking at Denver or Omaha. I personally know two teen girls who are seeing psychiatrists or psychologists. Their younger brothers tend to follow. And two other girls in long term, out-of-state psych wards.
It's dose dependent. BEFORE they have devices (which, again, you should avoid like the plague) get Google WiFi and time-limit their access. If you own a TV, throw it away now. My wife threw ours out in 2007. Best decision ever. We eventually bought a projector, but it only works if it's dark enough ... Which is not much of the day.
Get a lockbox. Put it at the front door. Sometimes, shit's gonna get real and you'll need rules like "Devices go in the box when you get home", "Devices go in the box until homework is done", or "Devices go in the box and hour before bed". You should also have them reflect, even journal, on the experience so they concretely incorporate the knowledge of how they feel with and without the phone.
Once they are in either middle school or high school, encourage them to take notes in bound notebooks. My daughter prefers spiral college rule 8x11, my son prefers Leuchtturm A5 color-coded by subject. Tell them you will keep those notebooks for them until they are old enough to store them themselves.
Encourage paper books.
Buy subscriptions and shun any company that serves ads despite having paid for the subscription.
Take long walks. Get a dog. Get two. Take your kids out into the world. A lot. Every weekend.
Fuck kids sports. My daughter's gymnastics coach broke the Nasser story. Fuck kids sports. The adults are awful. High school sports are pretty healthy. JV is fine. Kids need a lifelong love of exercise, not ACL repairs in high school (record I've heard is a girl who got 7 ACL repairs before graduating college).