Yes, DIRECTORS is a Scrabble word!

Letter values in Scrabble US: D 2, I 1, R 1, E 1, C 3, T 1, O 1, R 1, S 1.

Is it a valid word?

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

someone who controls resources and expenditures
member of a board of directors
someone who supervises the actors and directs the action in the production of a show
the person who directs the making of a film
the person who leads a musical group

Also: managing director, theater director, theatre director, film director, music director.