Yes, DUCKWEED is a Scrabble word!

Letter values in Scrabble US: D 2, U 1, C 3, K 5, W 4, E 1, E 1, D 2.

Is it a valid word?

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

any small or minute aquatic plant of the family Lemnaceae that float on or near the surface of shallow ponds