I used to drive around with my friends and goof off on the road. Although I do not have teens, here are some things that I've learned and may make it more real to your teens.
The first thing is to leave early. My husband's dad told him and my husband is going to tell our boys, you're better late than never. If you are running late, showing up 20 to 30 minutes late is not going to kill you. I always used to be in a hurry. You want to know how to not be in a hurry? Leave early. This day and age almost all of us have cell phones. If you can't bring yourself to leave early, set the alarm on your cell phone about 15 to 20 minutes before you are supposed to leave. That way, you know to pull everything to a finish and leave. And also, there is a point that you are running soooo late that you will never make it, so why hurry?
Another thing that my husband is going to pass down to our boys, is never trust a turn signal. That's a no brainer and not much to really worry about. It's just if you make them aware of other's stupidity, than they may be more aware of their own. Let them know when people do stupid things and what things it could have caused.
A real thing for me is when I had kids. I started driving way more safely. Even when they weren't with me, I started being more aware for the other driver. Notice I did say aware FOR the other driver, not OF the other driver. The reason being is that if you are aware for them you care about what you are doing because you would never want to hurt any small children in car seats that you may not be able to see inside the car. Not to mention that 60% to 80% people don't even use car seats properly anyway. So if you think that if someone is driving like an idiot they deserve to hit you because you will sue them, do their kids deserve the trauma? No.
A lot of things have changed from when I started driving; not driving rules, but for me personal. Getting married and having kids is a big one. It is totally different when you have someone depending on you. When I have my kids in the car, sometimes I just like to sit back and enjoy the scenery and not hurry. I like driving down the road feeling like I don't have a care in the world. Also, when you have known what it is like to be in a hurry, why not let the other person go first. For one, you'll be sure not to hit them, and second, maybe you'll start to feel good about becoming a better person by being kind and noticing others.
If all else fails, get on the internet and Google pictures of bad automobile accidents. Some pictures and horror stories may stop them in their tracks.