Yes, SQUADRON is a Scrabble word!

Letter values in Scrabble US: S 1, Q 10, U 1, A 1, D 2, R 1, O 1, N 1.

Is it a valid word?

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

a cavalry unit consisting of two or more troops and headquarters and supporting arms
an air force unit larger than a flight and smaller than a group
a naval unit that is detached from the fleet for a particular task