So lets say that law was around couldn't my friend technically be prosecuted by lets say my parents if I was a minor?
Any person with any common sense would never try to convert a minor. Not all people have common sense though. We're generally pretty safe as Hindus because in we don't do much more than answer questions when asked. We might go further if someone gets persistent, and asks a lot of questions.
If I would have ever had a student who was serious about it, first thing I would have done is call the parents. Otherwise, indeed, there could be big trouble.
But yes, that is another vulnerable group in India. If you build the school, you have some claim as to what you can say in that school, I suppose. Even here in Alberta we have two school systems, public, and Catholic. The Catholics do quite a bit of advertising about their 'acceptance' of diversity, but most people see through the guise. Saying the Lord's Prayer every day, even if you have no clue as to what it means, must have some impact.