His mother has sighed him out of school.
Generally, there is no age when a child is emancipated in New Jersey. A child is generally considered emancipated when they move out of their parents' home, join the military, get married, or otherwise no longer rely on their parents. Child support can be extended beyond high school or the age of 18 depending on the child's needs. For example, parents are required to contribute to their child's college expenses. A parent may have to continue to pay child support for a child who enrolls in college full-time immediately following high school. If a child drops out of college, then the parent paying child support may file a motion for modification of child support and seek termination of child support if the child is no longer enrolled in school full-time.
DISCLAIMER: Please be advised that this is general information for informational purposes only and does not constitute legal advice, nor does it create an attorney-client relationship. It is strongly advised that you contact a local attorney to obtain legal advice specific to your case.
Elder Law Attorney
At age 18, the assumption is that the child is emancipated, although it is certainly possible to prove otherwise. It would be possible to move to emancipate the child, although you'd have to show why the child is now independent. The Court isn't going to emancipate the child just because they're out of school, if they're a minor.