Yes, CHARADES is a Scrabble word!

Letter values in Scrabble US: C 3, H 4, A 1, R 1, A 1, D 2, E 1, S 1.

Is it a valid word?

CHARADES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

player acts out a phrase for others to guess
a composition that imitates or misrepresents somebody's style, usually in a humorous way
a word acted out in an episode of the game of charades

Also: put-on.