Classroom management... just as important for the success of any French teacher as the teacher's fluency! What are the things that drive YOU crazy in class and suck up your teaching energy? I'd always prefer to focus on teaching rather than dealing with situations, but of course they come up regularly, and I try to use them as teachable moments as well.
Have them make an appointment to come discuss their concerns with you outside of class time. Do it right within your plan book, agenda, or scheduling tool within your handheld computer (aka iPhone, android or tablet). If it's important enough to say, it's important enough to carve out time for and to phrase properly! This could be during lunch, recess, or after school... whatever works in your case.
I'd love for you to share here what other strategies have worked for you.