Theo Curle and Alexander Murray campaigned for their school, Blanchelande College, to plant a tree to symbolise the importance of protecting the planet.
The boys chose a Copper Beech tree to be planted, as they live for several hundred years.
Alexander and Theo, who were in Year 6 at the time of their project, did school assemblies on the importance of looking after the world, including buying sustainably, and the negative impact of deforestation.
The pair campaigned to persuade Guernsey Trees for Life to give them a sapling to plant, as they realised more trees are felled than planted annually.
School Librarian Jenny Toerein says the boys have more plans for the copper beech.
"Their plan is to collect seeds from this tree and send those trees out to other schools, potentially across the world."
The tree symbolises how one small action can make a big difference in the community.
The pair decided to dedicate the tree to the Royal Guernsey Light Infantry.
Jenny Toerein says when you plant something that will last a long time, it's important to think about remembrance.
"When we were talking about dedicating the tree, we were talking about how Guernsey Royal Light Infantry fought for something special, they fought for our freedom.
"They wanted the tree to be something that inspired people to fight for the environment and to fight for our future."
Other children in their year group looked for signatures for twinning school toilets with other facilities in the world where sanitation is scarce and for fire-fighting kits in the Amazon.
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