One thing you can do is combine baserunning with hitting and/or fielding to give them more experience. For example, if you're working on ground balls, put runners on base and let them run when you hit the ground balls. Good for the runners, good for the fielders to give them the feeling of how long they have to make a play. Make corrections as you go along.
You can also mix in fly balls and what to do in those situations. If you don't have enough girls on the team for full fielding, just use half the field or one outfielder or whatever you need.
The key is to take what you're doing in one area and add baserunning to it. Just be sure to rotate everyone through so you don't have some kids who get no practice running because they're always fielding. Good way to develop fielders as well.
You can also mix in fly balls and what to do in those situations. If you don't have enough girls on the team for full fielding, just use half the field or one outfielder or whatever you need.
The key is to take what you're doing in one area and add baserunning to it. Just be sure to rotate everyone through so you don't have some kids who get no practice running because they're always fielding. Good way to develop fielders as well.