Yes, SETTLEMENTS is a Scrabble word!

Letter values in Scrabble US: S 1, E 1, T 1, T 1, L 1, E 1, M 3, E 1, N 1, T 1, S 1.

Is it a valid word?

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

a body of people who settle far from home but maintain ties with their homeland; inhabitants remain nationals of their home state but are not literally under the home state's system of government
a community of people smaller than a town
a conclusive resolution of a matter and disposition of it
the act of colonizing; the establishment of colonies
something settled or resolved; the outcome of decision making
an area where a group of families live together
termination of a business operation by using its assets to discharge its liabilities

Also: small town.