Rochford Secondary Modern School opened on Rocheway in 1937, providing local children with a practical education geared towards employment.
The school closed in 1940 during the Battle of Britain, with many students evacuated to the Midlands and other areas. It reopened towards the end of the Second World War and, under Mr Wallace Cox, Miss Burnham and several retrained ex-servicemen, developed a strong reputation for sport and drama.
Rapid housing development in the 1950s led to significant overcrowding. Overflow classes were accommodated in local venues including the British Legion Hall, Congregational Church Hall, St Andrew’s Church Hall, The Oxford Club in Vaughan Close, and classrooms at Holt Farm Primary School. The curriculum adapted to these conditions, with students moving between sites for lessons and activities. Practical subjects such as gardening, rural studies and beekeeping continued alongside more formal academic work.
Growing enrolment and the national move towards comprehensive education in the 1960s led to the amalgamation of Rochford and Wakering secondary pupils. In 1961, The King Edmund School (KES) was established, welcoming students of all abilities from a wide area.
During the 1970s and 1980s, sport, drama and extracurricular activities flourished, alongside expanded work experience programmes and stronger links with local employers and post-16 institutions. Despite challenges—including storm damage and severe winter closures—the school adapted to the introduction of GCSEs and the National Curriculum, growing into one of the largest schools in Essex with an expanded leadership and administrative team.
In 1993, Mr Graham Abel became Head teacher, overseeing independence from local authority control and significant campus development, including new science, sports and Sixth Form facilities. Specialist status in Business and Enterprise was awarded in 2002, followed by the addition of a full-size all-weather pitch in 2005. After Mr Abel’s retirement in 2010, Mr Jonathan Osborn succeeded him and led the school’s conversion to academy status in July 2011. The school celebrated its fiftieth anniversary that year with a community event in 2012.
In 2020, the school was unexpectedly affected by structural issues identified within the main building. This led to the launch of a complete redevelopment programme under the Department for Education’s Building Schools for the Future initiative. The first phase opened in September 2026 with the Hawthorn Building, providing a new school hall, technology rooms, art studios, an activity studio, classrooms and offices. The second phase will replace the remaining older buildings, creating a campus-style environment with a new sports hall, Sixth Form facilities, science laboratories and dining areas.
In September 2026, Ms Jo Ingate was appointed as the school's first female Headteacher, leading the school into the next stage of its redevelopment and growth.