I give my kids in the back a wireless mouse and let them poke around on the center console, which they can see from where they're sitting.
It also solves the lack of voice commands Tesla doesn't have, and is a Super Siri. I just ask my kids to do things and they carry it out for me without having to take my eyes off the road.
They will also google around and find wiki pages for places we're driving through and read aloud facts and sights, we've often found interesting tid bits about places that cause us to stop or navigate toward and check things out. Things you'd otherwise never know about and blow right by..
$10 solution. Way more flexible, fun, and engaging with your passengers who might otherwise just be poking around on their smartphones facebooking their lives away to oblivion.