Most teachers should have an alternative assignment. I am surprised that this even got put forth. Maybe in the 10th grade in some of the "CINO" Catholic schools which have long since only paid 'lip service' to Catholic teachings, but 6th grade?
I would ask for my daughter to have an alternate assignment and I would want to know exactly what the lesson plan around these books was. Is it to point out the ERRORS of the books and to give instead the correct Catholic teaching? That would be good--but since this is a 'summer' reading, your poor child has to wait 2 months after reading that pathetic drivel to hear it denounced. Not good. If the teacher wanted to rebut the books they should be read at the beginning of the semester and IMMEDIATELY the first day the teaching should be squarely based on pointing out the books' errors.
But if this is the usual sort of "Pop Christianity' whereby the little angels are supposed to have 'open minds' and to be aware that the Church is not really all that great and St. Dan Brown is just pointing out exciting possibilities based on TRUTH. . .then you have a real problem. Something to bring up not only in front of the teacher but in front of the entire school board and even the diocese if necessary. You probably have a diocesean newspaper too, often with on-line versions. That can be used too.
I always used to be the 'good mother' who would, when faced with these kinds of situations, be told, "Trust us, we know best."
I learned. Now I'm the 'bad mother' who makes noise if I have to. I don't mind looking like a troublemaker. I always think, "If the world hates you, remember it hated Me first" --(thank you Jesus for those encouraging words). I don't have to win a popularity contest--I have to do my job as a parent and that means that if there is trouble, I will (politely but implacably) insist on TRUTH.
I'm tired of our children being used as guinea pigs by educators who should know better. I'm tired of having my authority as the person responsible for my child's education sabotaged by the people who should be helping me. Teachers are public SERVANTS. . . you wouldn't know it by the attitude of SOME of them (and God bless the many teachers who are trustworthy and who really TEACH our students instead of indoctrinate or misinform or 'break' them instead). Our children don't go to school to be 'jerked around' and to be thrown experimental garbage by these people. And especially in a Catholic school they are supposed to be learning AUTHENTIC CATHOLIC TEACHING.
And yes, I've read them. Heck, I've even read the whole "Left Behind" series (which a lot of people also found a 'good read'.) Depends on one's definition of good; (and please to whoever found them a good read, I am not picking on you). I happen to have read a lot of really outstanding literature in my life and therefore formulaic 'thrillers' just do not come across as a 'good read' to me. I think that it is a far, far better thing (points to you if you have read enough good literature to know the paraphrase WITHOUT GOOGLING) for children to be stretching their minds to really outstanding literature instead of 'sinking' to the merely 'popular'.