Hi there. Very sorry to hear this. Has your son been diagnosed with depression? Assuming so with his prescription for Zoloft. Has he been taking the Zoloft long? It typically takes about 6 to 8 weeks to work.
This must be heartbreaking for a parent. Is something going on? Is dad in the picture? Disengaging in school, ignorning personal grooming are signs of depression. If they are new especially.
I have noticed as being the parent of a 12 year old and 11 year old this month (birthday coming) that kids at around this age come to grips with who they are verses their perceptions of self that they have when younger. By this I mean, all students are kind of equal and all of a sudden, work is harder and some kids move ahead and some stay behind. This is hard for some kids and they then decide to do nothing school work wise or rebel against it. If their parents have expectations, for example, that they are these super great students and they are finding the work very challenging, instead of admitting that to their parents, they avoid doing it all together. My son has a friend like this. He flat out just just placed answers without reading questions on the recent state testing, when asked to write a paragraph, wrote one sentence, etc. Just flubbed the test. His parents have a hard time accepting him as a below average student and rather than disappointing them or failing, he just does nothing and rebels. This is new behavior for him this year in fifth grade.
Now, that may have absolutely nothing to do with your child, but just mention it because it is a time in which this type of attitude toward school may show up based on what I am seeing.
Anyway, is this new behavior for your son?
Well, the problem might be that zoloft is for depression, anxiety, and OCD among other things. The problem arises if the depression and anxiety are caused by ADHD or ADD, as Zoloft will only mask the symptoms and not treat the cause. And sometimes, if the child does have ADHD, being only on Zoloft can make things worse. I mention this because anxiety and depression are major co-disorders of ADHD or ADD.
Has he been evaluated for AD/HD?