Yes, IMPROVED is a Scrabble word!

Letter values in Scrabble US: I 1, M 3, P 3, R 1, O 1, V 4, E 1, D 2.

Is it a valid word?

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

made more desirable or valuable or profitable; especially made ready for use or marketing
become or made better in quality
(of land) made ready for development or agriculture by clearing of trees and brush