I have an 11 year old that can hit all 6 spots with her fastball pretty consistent and also has a great back hand change. Should I start teaching spins (Curveball, Dropball, Screwball) I bet she is throwing in the 42-44 range...
Fastball then Changeup then Drop
^^^This, the dropball is just an extension of the fastball and a fundamental pitch so it's the place to go. My 11YO DD sounds pretty similar (maybe a couple MPH faster but not much). The drop is an excellent pitch for her, just as fast as her fastball. Even on days when she isn't generating enough RPM for it to move much it's a good low fastball which is where a pitcher with moderate speed needs to locate most of the time anyway.