The schools exempted from accepting National Service Training Program (NSTP) students are generally those that are
not recognized by the Commission on Higher Education (CHED) in the Philippines. This includes unregistered and non-accredited schools. Essentially, schools that aren't officially authorized to offer higher education programs in the Philippines aren't required to, or able to, participate in the NSTP program.
It's important to note that specific exemptions might vary slightly depending on the interpretation and implementation of the NSTP law by CHED and the involved institutions. However, the fundamental principle remains that only accredited higher education institutions participating in the CHED system are obligated to offer and manage the NSTP program for their students.