Sorry if this post is long, but IMO you really need to understand why kids swing the way that they do in order to permanently fix the problem.
Phase 1: Most kids are born with a natural swing. I love to watch very young kids at the batting cage....the ones that have not had any meaningful instruction on how to swing. They all pretty much do the same thing....very similar to what your daughter does....drop hands straight down to get on plane of the pitch. This natural motion is not only an attempt to get the bat on the same plane as the pitch, but it also slots the back elbow....which is really the body bracing the rear arm against the back hip in order to gain leverage to swing the bat.
Phase 2: The local coach or hitting instructor will see her dropping her hands and start telling her to keep her hands up or to not drop her hands. This is the beginning of her athleticism being coached out of her....and it typically continues throughout her career.
The first step in fixing a problem is knowing what the problem is. The problem with your dd's swing is NOT HER DROPPING HER HANDS. I wouldn't say anything to her about her dropping her hands.
There are two idiot proof ways to permanently fix your dd's swing virtually overnight. One way is to become an expert on teaching the basic throwing motion and how the throwing motion relates to hitting. The second way is to go find an old tree and an old wood bat. Teach her how to swing the bat like you would an axe. Use some common sense. She doesn't need to swing full speed and hurt her wrist or arms. She should start with the bat between her feet with the barrel touching the ground similar to how you would start with a golf club. This starting position will also help her with her grip. Wrap the barrel with something soft if it makes to much noise when hitting the tree.
Both the throwing motion and the axe swing will teach her the proper sequence. I'm finding that the axe swing gets quicker results. There are some other advantages to using the axe swing that I can get into later if you want me to.
With the axe swing her hands will be starting down at about crotch height. She will swing her hands back up to about shoulder height. From there she will take the barrel to the tree. It should be one seamless motion with no pauses. When she does this you will notice she will NOT DROP HER HANDS when she begins the throw of the barrel at the tree. She should set up so that contact with the tree is made close to 90 degrees.
Obviously you can use other items to hit instead of a tree. Most kids think it's fun whacking a tree.
Once she gets comfortable, have her experiment with the position of her barrel as she takes it back. I like the kids to experiment with getting the hands and barrel to a position close to this:
View attachment 3897
Here is what a good ax swing looks like:
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If you don't like the idea of hitting a tree, you could always throw a bat into a net using the same starting position you would when swinging an axe. The only problem with doing that is that you have to retrieve the bat after each throw.
The main point to my post is that the easiest way to teach a sequence is by using an activity unrelated to hitting a ball. No tees, no front toss, no balls. You want them to focus 100% on the feel of a good sequence. They need to feel how their body is working. They need to feel the stretch. They need to feel the additionally loading that takes place when the hips and hands transition. They need to feel what it feels like to load and unload at the same time.
You can't do any of that if you're worried about hitting a ball.
Once she owns the sequence she will have to figure out how to perform the same sequence using her preferred batting stance. She will need to figure that our for herself. The absolute is the sequence. How players transition from their batting stance into the sequence is a style choice that each player needs to figure out for themselves.
The only rule is that the player has to be able to perform their sequence starting from their stance and get to a good ready to hit position ON TIME. If they find they aren't getting to a good ready to hit position on time, then they need to simplify their style.
Good luck.
Ok...I'm hoping this isn't a late April Fool's Joke LOL. At this point, I'll try most anything. We're going to work high tee, low tee, matrix, and try front and side toss as well. I think we'll get there. I would like you to elaborate a bit more on the "axe" drill.