Hey ,it depends on you mainly.If you can manage normal schools and coaching together and you're smart then you'll probably get through. But , there are many students in India who start their coaching from a really young age and there are many who are enrolled in dummy schools and attend full-time coaching. The thing to consider here is that they have put in double the time that you are putting in so there is huge chance of them getting selected over you,because Afterall it's all about the amount of practice.
In my opinion normal school are much, Much better in comparison with dummy schools. In dummy schools there is no urge to go to school. And the biggest drawback is that you won't have many friends and have very less real world experience. While, on the other hand if you're looking for developing your "self" then dummy schools and coaching are your best bet.(did you catch my drift?) The choice is yours - 'Self' or 'Society' ?