Chennai families treat Class 12 marks as more than a certificate: for state engineering admission it is the Physics, Chemistry and Mathematics marks that the cutoff is built from, so one weak paper costs more here than it does in most places. School choice is split between the Tamil Nadu state board and CBSE, and the two set very different papers even where the chapter names look the same.
That changes what tuition is for from Class 11 onwards. The work becomes as much about how an answer is written as about what is in it — the state board's papers stay close to the textbook, and answers written the way the book puts them tend to travel best, while CBSE asks the same content in a different shape. It is a fair question to put to a tutor early: which board have you taught, and for which classes.
Chennai is also a long city. Tutors on Tuitionites teach in Anna Nagar, Adyar, T. Nagar, Mylapore, Velachery, Porur, Tambaram and along OMR, in person and online, but Tambaram to Anna Nagar on a weekday evening is not a journey anyone keeps making twice a week for a full year. Families who want the sessions to survive the exam months usually settle on a mix — in person where the distance is short, online through the monsoon weeks when the roads decide otherwise.