Your options for a drive-in are limited, and none are ideal:
* Turn off the car completely: This is the safest and simplest solution. You'll lose your radio and climate control, but your headlights will be off.
* Park far away: If the screen's far enough away, your headlights might not be bothersome.
* Use very low beam (if you have that option): Some cars allow for dimming beyond just on/off.
Important Safety Note: Never attempt to modify the electrical system of your car unless you're knowledgeable about car electronics. Improper wiring can damage your car's electrical system or create a fire hazard. There's no safe, simple way to disable the headlights on your Grand Am without turning off the ignition.