Yes, DISPUTATIONS is a Scrabble word!

Letter values in Scrabble US: D 2, I 1, S 1, P 3, U 1, T 1, A 1, T 1, I 1, O 1, N 1, S 1.

Is it a valid word?

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

the formal presentation of a stated proposition and the opposition to it (usually followed by a vote)
a contentious speech act; a dispute where there is strong disagreement

Also: public debate.

Not playable in Scrabble US: DISCEPTATION.