Redbridge schoolchildren met Prince William outside Buckingham Palace during the Queen's Platinum Jubilee celebrations.
Pupils from William Torbitt Primary School in Newbury Park and Coppice Primary School in Chigwell helped to plant the final trees for the Tree of Trees last month.
The sculpture outside the palace was lit up on Thursday, June 2 as the principal beacon to launch the celebrations.
They were invited back to witness the switch-on and met the Duke of Cambridge.
Both schools had taken part in the Junior Forester Award, which saw children planting trees at school and learning how to care for them.
A Coppice Primary spokesperson said: "Prince William asked them about the kinds of trees they planted and whether they enjoy being out in nature.
"Some of them were a little star struck but spoke about the hundreds of trees planted at Coppice and William Torbitt this year."
Pupils also appeared on an episode of BBC show Blue Peter, which aired last week.
They met presenter Mwaksy Mudenda and were awarded green Blue Peter badges recognising their care for the environment.
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