An Australian friend told me that in their country, someone with a learner's permit will have an L on their license plate. After passing the driving test, they will then get a probationary (or provisional) license and have a red P on their plate for the first year, and a green P for two years after that. This way, everyone can see this is a new driver, be patient. I think that's a great idea. When I was taking lessons, driving the school's car, the vehicle had the words "instruction car" written on the back. Any driver's ed car will have that, or "student driver" on the sides. But there is no way to know from anything about my car that I just got my license, so please bear with me. I wish there was.