You certainly have good reason to be cautious! Your past experiences are contributing to your opinions, this is the case with all of us, our past experiences influence us. I am not certain from your posts if it is the classes themselves that bother you, or the fact that the priest is telling you what to do and you are resistant that is really bothering you…probably both.
I would like to offer you this. After you look over the books that your children will be learning from and have a chance to speak with the teachers…if everything seems okay then really consider enrolling your children. Obviously they are learning the faith at home, but it never hurts to have extra does it? Talking with your children after every class is also key.
If your priest is a good priest and this is a good program…perhaps there is something to be gained here, maybe even something you never considered. The Holy Spirit works in many wonderful and unseen ways. Perhaps you will meet a new family and a friendship will grow? Perhaps your children will meet a new friend? Perhaps it will help to further root your children in their faith and be a happy memory for them?
My children are homeschooled and I was resistant to enroll them in religious ed. However after having done so I am glad that I did. Are my children learning things they are not already learning at home? Well, not really but it is wonderful to have that “extra” reinforcement, my chidlren have made friends that they recognize at Mass, they enjoy the classes and I have been able to drop them off and spend quiet time in prayer or Eucharistic Adoration while they are in classes.
I will pray for you, this is not an easy decision. Ask the Holy Spirit where he wants your children. The Holy Spirit wants religious ed to be a positive experience, whether it be at home, at church or both. He truely knows what is best for your children. Take care.