The nearest I ever got to the school was via the zig-zag path and then only to the gate picking up a nephew that went to a pre-school group there in the early 1990s. That path shows up in the photograph. I'm sure Susan would welcome suggestions by anyone that actually used the school or pub as to where the coronation celebration was held and how people got there.Hobmoor Primary School was accessed in my time there 1954 to 1956 via an entrance by the side of the shops off Hobmoor Road and the first residential houses, you went in by the entrance next to the caretakers house. Not off Stoney Lane or by the side off The Yew Tree pub.
Incidentally the Margaret Green book has a class photo with a Mrs Humphreys in 1967 - after your time!