On a visit to the site in Calderbank, Airdrie, with Scottish Labour leader Richard Leonard, Mr Corbyn told the group they were doing "fantastic" work to preserve the space for future generations.
The Woodhall, Faskine and Palacecraig Conservation Group is campaigning to prevent a greenbelt corridor being built on by developers, as a planning application has been lodged to build thousands of homes at the site.
They want to take the area into community ownership to safeguard it for future generations.
Mr Corbyn was shown children's artwork at the site and praised campaigners.
He said: "For the next generation to understand that our world depends on the natural world, this is just such an educational resource for everybody.
"Well done to all of you for an absolutely fantastic campaign."
Thanked by the campaigners, he said it had been a "pleasure" to visit.
Campaign member Ann Glen spent time speaking with Mr Corbyn about the site said she was pleased by the Labour leader's interest in the campaign.
She said: "It will enhance the efforts that we are making to save this area to have someone who is the leader of the opposition, as of the present, to come here, a senior politician, to visit it."
"The campaign is about saving this area of greenbelt for posterity," she added.
"The concern is it will be trashed in a Los Angeles-style development of 2,600 executive houses, with some affordable houses, and commercial development which will suck the guts out of Airdrie - what guts are left of the place - and destroy this area forever."
Mr Leonard said: "The visit has been important because it shows that Jeremy Corbyn, as the leader of the Labour Party, is interested in community action to save greenbelt land.
"In the end this is a campaign which pitches a local community, who can only rely on organising the local people, against organised money.
"The Labour Party is on the side of this community and organising these people to see off big money interests to ensure that the environment and greenbelt space is preserved so that it is there not just for this generation but for future generations."