Yes, CLAPPED is a Scrabble word!

Letter values in Scrabble US: C 3, L 1, A 1, P 3, P 3, E 1, D 2.

Is it a valid word?

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

put quickly or forcibly
cause to strike the air in flight
clap one's hands or shout after performances to indicate approval
clap one's hands together
strike the air in flight
strike with the flat of the hand; usually in a friendly way, as in encouragement or greeting
strike together so as to produce a sharp percussive noise