Complex sentence: By the 1930s, the school had achieved a reputation for pioneering educational work, and in 1936 became a public school, but in 1948 the Governors accepted voluntary controlled status, which meant being funded by Wiltshire County Council as local education authority and accepting its supervision.
Split into simpler sentences: By the 1930s, the school had achieved a reputation for pioneering educational work, and in 1936 became a public school. In 1948 the Governors accepted voluntary controlled status, which meant being funded by Wiltshire County Council as local education authority and accepting its supervision.