Apparently the decision imposed on you to teach Maths was to prepare a ground fr termination?
Did you record demands of submitting resignation (audio/visual) or submitted representation in writing covering the demand? Do you have any witness?
Is the school a profit making establishment and Has the school registered under West Bengal Shops and Commercial Establishment Act?
Apply your resources and find out.
It should have displayed the registration certificate near entrance.
Teachers as per various judgments are not covered as a ‘Workman’ as in ID Act.
The school is affiliated to which Board?
Did the school, governing council issue any stinkers, notices, show cause notice to you and did you reply?
Are you member of united teachers associations?
You may download the service rules as per the Board guidelines, State Education Act, Directorate of Education and consult a competent and experienced Labor Consultant/Service Lawyer., show all docs and give inputs in person and proceed under expert advice of your lawyer.