You might think that just blasting the A/C on max is the fastest way to cool things down, but it's actually a little more nuanced than that. The people at Thrillist ran an experiment where they tried to cool down a hot car using four different methods:
1. Blast the A/C but keep the car parked the whole time.
2. Blast the A/C and drive with the windows down.
3. Blast the A/C and drive with the windows up.
4. Roll the passenger window down . . . fan the car with the driver's side door . . . then blast the A/C and drive off with the windows up.
And they found that the fastest way to cool down your car was actually option #4 . . . where you roll down the passenger window and fan the car with the driver's side door about a half dozen times.
Apparently that creates a low-pressure system that literally sucks the hot air out of the car.
It cooled the car at a rate of about 3.6 degrees per minute. Which was half-a-degree better than the next best option, blasting the A/C and driving with the windows up. Now you know.