Twelve million South African schoolchildren sang Happy Birthday to anti-apartheid icon Nelson Mandela as he turned 94 on Wednesday.

Mr. Mandela, who is retired from public life, is spending the day with his family in his southeastern village home of Qunu.

Meanwhile, people around the world are dedicating 67 minutes of the day to volunteer projects for the needy — one minute marking every year of his public service.

Mr. Mandela became South Africa's first black president in 1994 after spending 27 years in prison fighting the racist apartheid government.