The award is given to schools which excel in their eco-concern. They must meet strict criteria, including having a detailed action plan and a team to oversee its implementation. The pupils take the lead.
Environmental co-ordinator is class teacher Nicola Carse. She is already working hard with pupils to see that the school will hold onto its award when it is re-evaluated in two years' time. "When we got our Green Flag, we were given advice from Eco-schools and they come up with suggestions for things we could work on," she explains.
"Every year we carry out an environmental review, so you review work that is on-going and look at areas for improvement. Then the pupils and I sit down and come up with an action plan.
"Last year, they came up with the idea of having a garden. They developed the Green Team Garden where they grow vegetables. It has really come on and they enjoyed it. It was an add-on to the action plan, which they are keen to continue."
Other successes which the pupils pushed through on the way to achieving the Green Flag were recycling areas in every classroom, such as paper, plastic and composting bins. For the most part, it is up to the children to carry the message home to their parents.
For these lessons to be a success, Miss Carse believes they must be put into action outwith school. "The pupils are learning how to live a more sustainable lifestyle," she says. "There are a lot of tools out there to help and the pupils are getting a lot from it. Sometimes in larger schools, though, it can be difficult to keep the momentum going."
Along the road, Pencaitland Primary has managed to keep the ball rolling. It recently passed its re-inspection to keep the Green Flag award. Two years on, depute head Shirley Swinton, who heads up the school's eco effort, says: "Initially, it is a lot of work. It's about finding things that we can sustain, such as recycling paper, buying recycled materials, switching off the electricity and monitoring the consumption."
They try to integrate the eco message into the curriculum. So there is a dedicated section for it, but there are other things like science, environmental studies, history, and so on that they can also use.
"For instance, if they were doing a Second World War project, we would look back to see how people recycled then, because at that time it was important that you make do and mend things. In that respect, recycling is not a new thing."
And, she says, there is evidence that what the staff have started as lessons, the children are continuing in practice.
"We get children telling people to switch off lights for instance, we see children being more economical with the resources in the school, such as paper," she says.
"They have a greater understanding and a greater respect for the resources that they are using, because they know that they shouldn't waste them, and they understand the implications of waste."