Hi Viktoria.
The two beech trees that were planted are on the green in front of the children and would have been clearly in view on the uncropped version of this photograph, had they been there. As they were supposed to be planted as memorials to the Silver Jubilee of George V (or the Coronation of George VI) there would have been many local people present. And the green was (and is) a popular play area for local children.
I have a similar postcard postmarked 1909, obviously much earlier, but with the similarity of fence and trees, albeit since grown and trimmed somewhat. Difficult to judge, but with what you suggest as regards the children's clothing, I shall probably end up putting an approximate date of 1925 - 1935. Unless anything else comes to light.
Personally, if it wasn't for the Beech trees, I would have put the clothing at post World War II. But that's why we use this Forum. There are always people who can help.
Many thanks for your help, Viktoria,
from Scobie.