I have a graphics project for school and the task is to design a board game. I need to work out a system by which two players can simultaneously make a secret choice between two options and then present their choice at the same time. I have thought about making a little arrow that can be spun around and then moved by the player to the choice they want to pick, hidden behind a screen, but it just feels a bit messy. And using cards that can be placed down seems to be a flawed system because as soon as one card becomes scratched and identifiable the whole game becomes unplayable.

I would really appreciate any suggestions you may have as to how to do this.