Pitch to contact. That's a great idea. Like last fall when she lost a game 23-1 and gave up 0 walks, and 3 earned runs. Or last Spring when she gave up probably half a dozen walks all Spring and lost every game.
I don't know why I didn't think of that.
She gave up 0 walks and 3 earned runs, but her team lost 23-1???? It sounds like the problem is not with her pitching, but with the defense behind her!!! It almost sounds like you want her to strike everyone out, so the ball never gets in play. Lot of pressure to put on a 12 year-old.
At 12U, unless she is an unusually dominant pitcher, the ball is going to be put in play very often. She needs to be able to rely on her defense to get outs. You can't expect her to carry a lousy defense with her pitching.
Generally at 12U a pitcher can't win games by herself....but she can certainly lose them with walks & passed balls. Again, have her focus on hitting spots, and changing speeds.