The batter should look at the fielders and see where there are soft spots. If 1B is not charging, then you might want to go toward her. If 3B is playing deep, you might want to go there. You can try the pitcher if she is a weak fielder.
As the kids get older, it becomes more and more difficult to get on base bunting.
I assuming the lead off batter is a fast runner, so I would have them drag bunt down the first base line. A lefty is already on the run when drag bunting, so a better chance of out running the throw. First baseman has to take time to turn completly around to make the throw.
JMO
I teach the younger levels not to try and bunt down the lines. I want the ball bunted towards the SS or 2B. We want the ball to be in a place where the 1B, P, C or 3B, P, C all have a chance at fielding it. Usually, they all look at each other and it is too late to make a throw after they decided who is going to pick it up. It is also easier for the hitter to get a bunt down in fair territory instead of trying to lay one down the line. We will call which side we want the bunt depending on the defense.
Yup - but on the second time around - first time the 2B may get caught napping and not break early enough. After the first bunt attempt (even within the same at bat - the 2B will be breaking early to cover 1B.
If F3 is crashing and you can push it past F3 and F1, all you have to do is out run F3 and F1 to first base. F4 can either field the push bunt or cover first but she can't do both.