...gather the FNG's and a brand new ambulance in a parking lot. One by one, each Newbie (no one riding shotgun) drives the ambulance through drills; most of which should be in reverse. Familiarization with turning radius, slalom-type maneuvers, emergency braking (wet and dry) should all be done with the liberal use of traffic cones.
You've all heard this before but my only modification is that your fellow FNG's be the traffic cones.
That would be a very effective approach. Our company everyone has to take turns being strapped to a long board on the cot while someone else drives. It's amazing how quickly some people improve their driving after getting off the cot.