You are very much covered for Service Tax under Commercial Coaching or Training Services
In the following circular department has clarified the same
Circular No. 59/8/2003, 20th June, 2003
Whether individuals going to houses to impart tuition/coaching would be chargeable to service tax: It is clarified that service tax is on institutions/establishments. Therefore, only those service providers are covered under the service tax who have some establishment for providing commercial coaching or training i.e. institutional coaching or training. Thus, individuals providing services at the premises of a service receiver would not be covered under service tax.
However, if coaching or training center provides commercial coaching by sending individuals to the premises of service receivers, such services would be chargeable to tax, as in this case, the individuals are rendering services on behalf of an institution.
In your case you are providing Training on Behalf of your Firm, which has an establishment setup
So, you need to register with Service Tax Dept, once your turnover exceeds 9 Lacs
You can claim 10 lacs exemption for first year, but registration has to be done after exceeding 9 lacs