When was Surbiton County Grammar created?

There's no school called "Surbiton County Grammar." It's possible you're thinking of one of these schools:

* Surbiton High School: This independent school was founded in 1893.

* The Tiffin Girls' School: This grammar school in Kingston upon Thames was founded in 1884.

* The Tiffin Boys' School: This grammar school in Kingston upon Thames was founded in 1881.

Could you please clarify the name of the school you're interested in?