The group, aged between 11 and 16 years of age, will spend nine days in a Buddhist temple mirroring the exact number of days they survived before being found by divers inside Chiang Rai’s Tham Luang Cave.
Their act will honour former Thai Navy Seal Saman Kunan who died after running out of oxygen during a rescue attempt to lay air tanks along the evacuation route on July 6.
Thai officials said Ekapol Chanthawong, the 25-year-old coach trapped with the boys, will be ordained as a monk.
A twelfth boy will not participate as he is a Christian.
Prior to having their heads shaved, the Wild Boars offered prayers in a religious ceremony at Wat Phra Thart Doi Wao temple in Mae Sai district, Chiang Rai.
They lit candlesticks and placed sweets, fruits and sugary drinks in front of Buddha statues.
When were the Thai boys rescued?
The young footballers and their coach were freed from the cave’s labyrinthine of tunnels during a complicated three-day rescue ending on July 10.
They became cut off by flash floods on June 23 after ignoring a sign outside the entrance warning people not to enter during the rainy season.
British divers eventually found the boys perched on a ledge in complete darkness after the Thai government sought help from the international community.
A round-the-clock operation was launched involving dozens of divers and hundreds of volunteers.
The boy, who spent 18 days inside the cave in total, were reportedly sedated as they were pulled along narrow passageways by expert divers.
Their rescue was met by huge cheers while millions of people around the world followed live reports of their progress.
As part of their rehabilitation, they spent a few days in isolation in hospital but returned home afterwards.
At a press conference last week, they revealed the steps that kept them alive.
These included drinking dripping rainwater from stalactites.
They also offered numerous apologies for going inside the cave and for the worry they had caused their parents.
Why are the boys become ordained?
The practice of becoming ordained is believed to bring blessings and honour to Thai Buddhist families and is a common practice in the country.
More than 90 percent of Thailand’s population follow Buddhism.