Smartwatch without apps but with limited phone, texting, and location sharing to trusted contacts appears to be the way out offering most technical benefits without becoming a firehose of horribleness, addiction, and distraction.

Dumb / kosher phones seem like another idea but have the disadvantage of being another thing to loose and break rather than something that's strapped to them.

Another thing is to role-model and reinforce smartphone etiquette by not pulling them out to waste time when around other people.

I applaud keeping smartphone, social media, screen, and computer privileges minimum age as high and restricted as possible for as long as possible.