Leon Hoyle died on August 7 2017 after falling through a roof on Lune Industrial Estate while playing with friends.
Leon, who attended Central Lancaster High School, was a regular at Marsh Community Centre, and friends have now made a special memorial garden in the centre grounds.
The youngsters designed the memorial to include an orange rose bush and flowers in Leon’s favourite colours.
They were joined in their work by Marsh PCSO Cath Elliot.
On the centre’s Facebook page, organisers said: “We are so proud of all the young people that helped out as well as our local PCSO Cath.
“They have all worked together to make a memorial garden to remember the beloved Leon Hoyle.”