Field trip to our local police station for a tour. The officer gave an age-appropriate tour, including the holding cell, the firing range and the motorcycle garage. It made a big impression on the girls.
Have someone in authority, principal, police officer, fire fighter, etc, talk to the girls about what it means to have their job and how people depend on them.
We made a trip to the fire department. They gave us a tour, allowed the girls to try on their uniforms, and squirt the fire hose. They talked about fire safety. We made them a special card to thank them. We also decorated all of their chalkboards while we waited for them to return from a fire.
The girls play a version of simon says. In this version, the girls only obey Simon if Simon is wearing a hat of authority, which we defined as a police hat, fire hat, or teacher hat. For the teacher hat, I took a cloth hat and labeled it "teacher".
We brought lots of dress-up hats and kept swapping hats between hats of authority and silly hats (i.e. moose antlers, Donald Duck, Minnie Mouse, crown, hardhat, pirate hat).