Mr. Sumanbaner,
Are you sure the School have obtained registration under the EPF &MP Act, 1952. If yes, then they might be depriving few employees from the benefit of the Act and all the employees if the reply is negative.
In both the cases, just submit a complaint to the Regional Provident Fund Commissioner and Area Enforcement Officer of the Employees Provident Fund Organisation either severally or jointly mentioning name and complete address of the school, your date of joining, rate of pay etc. and appropriate action will be taken by the authority concerned.
Regards
P K Sharma