Bryn supplied an example from 1947.
Rock paper scissors is the most common English name for this game of symbolic hand gestures, but according to the OED’s current evidence, it isn’t the earliest one. Scissors paper stone (1932), Roshambo (1936), and janken or jan ken pon (from at least 1906 in the OED‘s files) are all attested significantly earlier than rock paper scissors, which our entry traces back only as far as 1954:
1954 Lima (Ohio) News 27 July 10/1 Games of the Orient such as Japanese tag and Jan, Kem, Po (rock, paper, scissors, in American!)
Can you help us find an earlier example of rock paper scissors?
Posted by OED_Editor on 5 December 2012 14.16