Taught alot of youngin's to drive over the years cause the parents had no patience. Driving goes beyond point the tires and go...
Give confidence, but make them respectful of the damage they can do. Nothing worse than seeing drivers that are scared to death behind the wheel. I don't want to be around them.
Neutral is there for a reason, don't be afraid to use it. Same with first and second gear, they have a purpose.
Threshold braking and acceleration and the use of neutral - on ice, heavy rain, dirt roads etc. All invaluable. Take them out in all conditions and let them abuse the tires a bit. Even now, first snow I get aggressive in quiet areas with the car, just a reminder of driving skills.
Teach them how to properly raise a car with a jack and change a tire at minimum. Drives me nuts to see kids waiting hours for AMA or other to help them. I learned at a young age to work on cars, saved probably 10's of thousands of dollars from DIY - and made alot working on other peoples cars.
Try to find someone with a manual, when you have to use all 4 limbs to drive, it enhances skills. Mind you it's not fun being with a beginner in a manual, always feel like you're in a rodeo riding a bull
Make it fun, not a chore, they are more apt to listen.