Problem children are part of the job at level 5, you can't get rid of them.
I've just cured a problem child. A message appeared at the end of the work day saying he's been cured and another the next morning with a thanks from the parent , as well as a $1,000 tip, but in that very same day a different problem child came after school.
By the way, I have no idea how I cured him. I didn't reprehend, didn't talk about problems, in fact I gave that child no special attention.
I'm looking forward for Carl's guide on this job, I'm more lost then a blind monkey in a wild west shooting.