1) What was the drill or technique that worked the best to help your daughter develop a consistent change-up. My daughter continues to struggle with command on her changeup.
2) For you, what drill or practice routine ( outside of improving mechanics ) that helped improve velocity.
My daughter is 15, 6'0 tall, has a nice curve, throws the rise and her top speed pitches are upper 50s. She goes to a good coach but I'm always looking for things that will help.
She has to find a grip she likes, once she has one she is comfortable with you just have to throw it. Last February my girl learned a new grip that she liked a lot, by spring my DD was not quite ready with her CU. So we just threw change ups every other pitching session, on the of session we mixed it in throw a couple FBs and then a couple CUs then a couple drops curves, then a couple CUs. But we focused our attention on the change.
One thing that seemed to help was putting up a string a bout 2 thirds of the way to the plate, she would try to get the ball over the string, and at the plate it would usually be about shin high. That helped her learn where to release so she wasn't bouncing them up there and wasn't hanging them out belt hight