Celebrations have been held across India to mark the centenary of the adoption of Vande Mataram as the country's national song.
Muslim girls singing Vande Mataram
Television channels beamed images of schoolchildren singing the song at the arranged time of 1100 (0530GMT).
The Hindu nationalist Bharatiya Janata Party started its national conclave with the song.
But several Muslim educational institutions boycotted the song, which has been at the centre of a row.
The controversy began last month after the central government said the song must be sung at all schools on its centenary.
After some Muslim groups said it was against Islam to sing it as it was a hymn to the Hindu Goddess Durga, the government backed down and made singing voluntary.
But the BJP insisted that the national song must be sung at all schools, including Islamic madrassas or religious seminaries.
Bankim Chandra Chattopadhyay wrote Vande Mataram
Many Muslim groups subsequently called on members of their community not to sing the song or to keep their children away from school on the day.
And although some Muslim institutions boycotted the song, many Muslim schools across India participated in the celebrations.
The song was sung in educational institutions in the states of Madhya Pradesh, Gujarat, Chhattisgarh and Rajasthan - all ruled by the BJP.
But in the southern state of Tamil Nadu, none of the government ministers participated in the celebrations. Many minority educational institutions there also abstained from the celebrations.
The song, written by Bengali poet Bankim Chandra Chattopadhyay in 1876, was first sung at the Congress Party session in Varanasi in 1905.
Vande Mataram, which translates as "Mother, I bow to thee" or "hail to the mother", became the rallying cry for Indians fighting British colonial rule.
The song was tipped to be India's national anthem, but lost out to Nobel laureate Rabindranath Tagore's more secular Jana Gana Mana following opposition from Muslim groups.
But Vande Mataram is still regarded highly and the song is played in parliament at the end of each session.