Yes, OWL is a Scrabble word!

Letter values in Scrabble US: O 1, W 4, L 1.

Is it a valid word?

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

nocturnal bird of prey with hawk-like beak and claws and large head with front-facing eyes

Also: bird of minerva, bird of night.