If your bank refuses to open an account in the name of a minor, you can approach a post office or nationalized banks like the State Bank of India, Punjab National Bank, Central Bank of India, Syndicate Bank and private banks like HDFC Bank and ICICI Bank.
You can open in post office, see more details below -
Limit of subscription:- (1) Any individual may, on his own behalf or on behalf of a minor of whom he is the guardian, subscribe to the Public Provident Fund (thereafter referred to as the fund) any amount not less than Rs. 500 and not more than Rs. 70,000 in a year.
Source - IndiaPost