[alephnerd]

I'm not sure NCERT will ever be able to teach about ethnic diversity within India correctly - it's too politically loaded. For example, I'm Pahari. According to NCERT, we're a Hindi speaking ethnic group, though our Pahari languages are completely indecipherable to Hindi speakers (Eg. Sadh khol lal nukke heghe. Chaiyda tenu?) and we are classified as a different language group from Hindi. Similar reductiveness is applied to the "Hindi Heartland" by removing the ethnolinguistic diversity of Central India (eg. Bihar historically wasn't Hindi speaking until the 1970s because of Hindi oriented literacy programs).

If it's bad enough for highly represented regions of India, imagine less well represented areas like the North East, the Ghats, etc.

The big issue is NCERT and most grade school Indian historical education takes a very "Delhi" centric view of Gupta-Small Kingdoms-Delhi Sultanate-Mughals-British-Independence, but this chronological ordering is true for only a subset of India. South Indian kingdoms (itself a problematic term), Indigenous movements, the entire ethnographic history of the Northeast and the Northwest, etc all get ignored. That said, this is a bipartisan problem - doesn't matter if it's INC, BJP, whatever who's in power.

Also, there is a dearth of qualified teachers for the CBSE curriculum.