The surf lesson Big Dyls (Dylan Cossey) from The Block NZ auctioned off for charity went for $1,000 last Saturday.
Mr Cossey was approached by Foster Hope, a charity who make up backpacks for children when they are removed from their home into foster care, to take a surf lesson for six people.
The lesson had steadily received bids to $250, when the last bid of $1,000 came in.
A spokesperson for Foster Hope said they were very grateful for Mr Cossey's support.
"And thrilled with outcome of the auction, the proceeds will go a long way to help out foster children in need."
Mr Cossey and his siblings grew up seeing foster children turning up to his house in the early hours of the morning, with rubbish bags holding their belongings.
He remembered his mother waking him and his siblings up in the middle of the night when a child arrived, they would all have a Milo and chocolate fingers and he would then show them their Lego.