I'd suggest going to a pitching coach and double checking her form. You could also try contacting a local college coach and ask to chat with the pitching coach or even a pitcher about form. Accuracy starts with good form, and if she has any bad habits, it could make everything else a struggle.

Then, start pitching a little closer and hold the target/glove in a different position for every pitch--even way out of the zone. There seems to be something about changing up the focus/site picture that helps.

Use step back games where she starts close, then has to hit three out of four corners before stepping back and trying again. Keep going as far back as she can go before she loses for (tries to throw/force the ball rather than pitch with good/loose form.) Another version is she has to throw 3 strikes before throwing 4 balls before she can step back. Keep track of her scores/distance for future goals.

Another fun game to use at the end of practice is putting a ball on a bucket or cone and giving her 10 or 20 pitches to to see how many times she can knock it off. You can start her closer up for more success, or use a big ball (volleyball or basketball.)

Again, I'd really suggest checking her form first--accuracy and speed are products of good form.

i suggest putting her on her knees. make her throw from her knees. this will help. u will need to do this for a while though. that's wht i'm doing right now. that is also how i got my change up back and under control into beautiful perfection

Another thing is that you should work on form BEFORE worrying about the speed of it

It's time to focus on her control. Every practice must be focused on control and accuracy. Check her mechanics maybe there are little movements which you might have overlooked.

Repetition is the key to nailing good pitches and consistency. Start with the corners until she can naturally do it and gets the correct of each pitch.

http://www.softballperformance.com/softball-pitching-drills-how-to-improve-your-accuracy/