Yes, COVERED is a Scrabble word!

Letter values in Scrabble US: C 3, O 1, V 4, E 1, R 1, E 1, D 2.

Is it a valid word?

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

provide with a covering or cause to be covered
form a cover over
span an interval of distance, space or time
provide for
act on verbally or in some form of artistic expression
include in scope; include as part of something broader; have as one's sphere or territory
travel across or pass over
be responsible for reporting the details of, as in journalism
hold within range of an aimed firearm
to take an action to protect against future problems
hide from view or knowledge
protect or defend (a position in a game)
maintain a check on; especially by patrolling
protect by insurance
make up for shortcomings or a feeling of inferiority by exaggerating good qualities
invest with a large or excessive amount of something
help out by taking someone's place and temporarily assuming his responsibilities
be sufficient to meet, defray, or offset the charge or cost of
spread over a surface to conceal or protect
cover as if with a shroud
copulate with a female, used especially of horses
put something on top of something else
play a higher card than the one previously played
be responsible for guarding an opponent in a game
sit on (eggs)
clothe, as if for protection from the elements

overlaid or spread or topped with or enclosed within something; sometimes used as a combining form

Also: spread over, pass over, get over, get across, cut through, cut across, cover up, wrap up.