The former couple, who split last March after 10 years of marriage, were spotted spending time with their children, Apple, 10, and Moses, eight, at the beach in Malibu, California.
A source said that the Coldplay frontman, 37, who is now dating Jennifer Lawrence, 24, and his estranged wife, 42, spent approximately two hours together.
But the insider told E! News that their reunion ''was nothing romantic for what it seemed, just surf lessons for the kids.''
Meanwhile, Jennifer spent the day in Boston, where she is preparing to start filming her upcoming movie, 'Joy,' alongside Bradley Cooper and Robert De Niro.
The couple were thought to have split in October, but a source previously insisted they only told people they had split so they could enjoy a relationship out of the spotlight.
The insider said: ''Neither of them wanted to be a public couple so quickly.
''So they told people they were broken up while they continued to build a relationship.''
Gwyneth, who is dating 'Glee' co-creator Brad Falchuk, 43, recently admitted she and Chris began making plans to separate in 2012 and ''worked really f**king hard to get to [this] point.''
She added: ''But we're very, very close, and it's so nice. I feel like it's, in a way, the relationship we were meant to have.''
Exposing some of the sickest songs of the iconic rock band's career.
Where does Billie place among the Bond theme greats?
On the 8th October 1980 Talking Heads released not only one of their most significant albums but also one of the most significant albums of the last...
She’s set to become the youngest to ever headline Glastonbury.
As the summer ended and Fall arrived, some great new releases dropped in September, including the first new music from ABBA in 40 years!
On the 1st October 1991 Prince, together with a new backing band - The New Power Generation, released his 13th full length studio album - 'Diamonds...
Olly Alexander AKA Years & Years pulls us into a sexy fantasy world in the trippy video for his latest single ‘Crave’.