Yes, ITEMS is a Scrabble word!

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

Is it a valid word?

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

a distinct part that can be specified separately in a group of things that could be enumerated on a list
a small part that can be considered separately from the whole
a whole individual unit; especially when included in a list or collection
an isolated fact that is considered separately from the whole
an individual instance of a type of symbol