cshilt posted some good drills. The top hand drill is one of my favorite. We developed a two handled bat for this, but the top hand drill is easier.
DD had lesson last night. He caught her rotating her front shoulder in a little when she loads. Which was limiting her seeing the ball and she was taking a big swing (drag). Easy correction, just going to take tons of bp to get it into muscle memory.
Thanks Mark. Vlads shoulder rotates in and down a little. Hers is rotating straight back and turning her chin/head away from the ball.