Line 9-inch square pan with whole graham crackers (breaking crackers if necessary).
Prepare pudding mix as directed on pkg. for pudding; let stand 5 minutes, then blend in Cool Whip.
Spread 1/2 the pudding mixture over the graham crackers. Add another layer of crackers, top with remaining pudding mixture and remaining crackers. Spread blueberry pie filling over top layers of graham crackers.