I have a relay drill that my players of all ages love.   It works on fielding and conditioning at the same time.   Best part is that the players really enjoy it and the competition takes away the dislike of doing sprints.

Softball Relay Conditioning Drill
One line foul pole to foul pole, distance between players depends on number of players. Optimally you need a minimum of 40-60 feet.

Goal is to accomplish two things:
1. Practice a front side relay from the outfield to infield.
2. Include some conditioning with the drill. That’s the part they really like!

Here’s how it works:
First player in line throws the ball to the second person in line, then sprints to the end of the line.
The players in the relay line attempt to relay the ball to the end of the line using correct fundamentals.
If the relay line drops or misses the ball, the ball returns to the point of the mistake.

The girls love it and really do not mind the 100 yard (plus or minus a little) sprint, because they WANT to win.