Recruitment/talent Acquisition, Career Counselling
By & large, the HR policies would be the same as for any Educational Institution--except that you will need to tweak the policies a bit to suit YOUR Institution.
Coming to your query ['where should the HR department implemented--for school or for Trust?']--obviously for the School, since this is where the employees work. The Trust can start another Institution--where again the HR policies related to THAT Institution would need to be tailor-made & implemented.
This is akin to something like Tata Sons Ltd being the Holding Company of ALL the Tata Group Companies--yet each of the Group Companies have their own set of HR Policy Frameworks.
Hope you get the point.
All the Best.
15th July 2013 From India, Hyderabad
15th July 2013 From India, Ahmadabad