I have no doubt the parish is using the resource it has, in terms of volunteer catechists, time, and space the best way it can, and hazard a guess that, as in my parish despite repeated appeals, no one has come forward to teach a class of older youth. The director probably had to make a choice to put her in a class of younger children which happens to be the makeup of the group this year, or with the adults, which is not recommended, because of the nature of the discussions on marriage and related issues that will arise.
In our parish I have to do this with the Spanish class, this is the first we have enough volunteers to separate adults and children, but I wish we could do more for the youth.
We have one person who will have a 2nd year class of 37 this year, grades 4-8, because I can’t get someone to handle the Jr Hi separately, finally got someone for High School last year. the major problem is time and space, as well as volunteers.
Most of the children in these classes are here because their parents never got around to performing their clear duty to teach and baptize their children, and the child is paying the price.
In my parish, I would have her join the confirmation class with her friends, or the regular 8th grade class which would provide a good intro to the doctrinal part and scripture, and have her join the special sessions on Saturday or Sunday for those adults preparing for baptism so she gets the RCIA part of it, make sure she is prepared for and participates at the rites in the proper time, more record keeping on my part, better experience on her part.
If you have any influence in this child’s parish, why not gently suggest that she be partnered with some of the teens who already have their sacraments as sponsors and mentors who will go through the class with her so she doesn’t feel alone. This is actually recommended in the ritual book. At this age, to enter a room without a friend in it is torture to a kid.
We do try to go the extra mile to make sure every one has the best experience, but we are drawn very thin.
I call again on all those self-professed experts (or muftis) on this forum to become part of the solution in your parish and be a catechist. If you are not doing so, I ask, why not?