Mr. McBeevee - S3-E1
Visible crew/equipment: When Barney, Andy and Opie go outside to see Opie's "horse" the microphone and boom shadow are visible on the back door.
Visible crew/equipment: At the end when Aunt Bea enters the courthouse, she doesn't close the door completely. You can see a hand from outside grab the door, and close it very slowly.
Answer: Those "boxes" are valences that used to be very common, before air conditioning. They allow for windows to be open during rain storms. They permit air circulation, without letting the rain in.