Nope, No Glass
In order for the crew to gain control over lights and reflected surfaces, the producers removed the glass from the sliding door which can be seen in many scenes on The Brady Bunch back yard.
Oh Really, Now?
The theme song for The Brady Bunch was originally recorded by the Peppermint Trolley Company. After the producers noticed the singing talent of the Brady children, they went on to record the theme song with the cast themselves.