If they are also the two fastest girls on the team (and are good base runners, too), then it is a no-brainer to hit them #1 and #2. The pressure two speedy slappers puts on a 12U defense is intense and it doesn't go away once they're on base. In fact, at 12U you'll often see outfielders still playing shallow after the slappers have concluded their at-bats because the steal threat they present messes with the defense's heads a bit. This can leave an RBI smorgasbord for the #3 hitter if she has some pop (and she should). Just remember to tell your 3-hole hitter to survey the defense and to be hitting the first pitch (if it's good) if she sees that the outfield hasn't gone back to normal depth.