a cardboard prop to look like a car
We had this one as well, four chairs arranged behind the cardboard to look like a group in service.
One of my favourites was the segment of the Theocratic News (in the KM, done one SM in a month).
The bros made a cardboard TV set, with a cut-out the size of the TV screen.
Speaker says, And now, with the Theocratic News, Br. Schmo.
Br. Schmo (inside mock TV): Good evening, ...
Also, with the written review, the review sheets were passed out, as well as pieces of thin pressboard, smooth on one side, to use as backing for writing the written review, The written review was passed to a neighbour for evaluation - the kids were always strict in marking each other's answers.