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The menu, featuring variety of dishes, is likely to include his favourite meal of samp and tripe.
His granddaughter Ndileka Mandela told Sowetan yesterday that during the lunch the family will present him with a cake.
Like a number of people around the world, including in South Africa, Mandela's family members will do their part and for 67 minutes improve the lives of the needy.
Some will be doing their bit in and around Qunu, Mandela's home village in the Eastern Cape.
"The big lunch will be at 4pm where we will present him with a cake. Our 67 minutes is a way of giving back to him, and that is our birthday gift to him," said Ndileka.
"We will probably have food like samp and tripe, his favourite food."
Winnie Madikizela-Mandela and her children, Zenani and Zindzi, will do their 67 minutes at the late ANC leader Oliver Tambo's home in Lusikisiki.
Madiba is turning 94.
Ndileka said the world's beloved statesman was in high spirits.
The family will wish him happy birthday in the morning before they leave to do community work.
His wife Graça Machel and some of his grandchildren, including Ndileka, kick-started the celebrations yesterday at No-Moscow Primary School in Qunu where former United States of America president Bill Clinton donated a mobile library and books.
Ndileka said the project to help the school was the idea of Mbuso, who is the son of Mandela's late son Makgatho.
"Mbuso came up with the project to help the school."
She said Clinton, together with his daughter Chelsea, accompanied the family to the school.
They then left to plant some trees where Machel had started a garden.
Ndileka said her granddad, who loves having all his family members around him, was yesterday beaming from ear to ear when he saw Clinton on his return from planting the trees.
Clinton's visit was the biggest surprise for Madiba.
"You should have seen his smile when he saw him, he just said '... Hi Bill, are you here?' He did not know he was coming.
"Bill Clinton came over to join the family for lunch. Granddad did not know he was in the country.
"He is visiting my granddad, every year he finds time to see granddad ... either before his birthday or after.
"But this time his visit has coincided with his birthday," Ndileka said.
She said they will also be going to a clinic in Qunu today with other family members where they will clean the clinic and donate a medical fridge, fax machine and other equipment.
ANC leaders will also celebrate Mandela's birthday. The party's secretary-general Gwede Mantashe will be teaching history for 67 minutes in Vosloorus on the East Rand.