DO you really think that a coach would not put his best 12 girls on the field? Even if the 7th or 8th graders were on varsity, they would play based on their ability to get the job done. To play a less skilled girl would be ludicrous. Now having an 8th grader and 10th grader all other things being equal, I may lean towards playing the younger player as I could get more years and development out of her. Let's face it if an 8th grader is as good as a 10th or 11th grader now at this point the upside to this player is greater. Many times an 8th grade travel girls with triple or more game (including big games in finals of tourns) that a non-travel but solid mutli-sport upperclassman. But there is much to be said for emotional maturity of a player as well. So many variables, and many ways to look at it. Depends on the coaches philosophy.