Yes, KAZOOS is a Scrabble word!

Letter values in Scrabble US: K 5, A 1, Z 10, O 1, O 1, S 1.

Is it a valid word?

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

a toy wind instrument that has a membrane that makes a sound when you hum into the mouthpiece