Sir William Robertson Academy (formerly Sir William Robertson High School) is a coeducational secondary school of around 1000 pupils, situated in Welbourn, near Lincoln, Lincolnshire, England. The school is sited on a former WWII munitions dump for the nearby Wellingore Aerodrome.

The school used to specialise languages and taught French, Spanish and German, but now only French is taught. From September 2012 the school has catered for students aged 11 to 18. The school also achieved its best ever GCSE results in 2008.

The school has four houses, each with a differently coloured tie: Seacole (yellow), Windrush (red),Robertson (blue) and Attenborough (green).

Sir William Robertson Academy is named after Field Marshal William Robertson, born in Welbourn, who served in the First World War.

The school was to open as Leadenham County Secondary Modern School. The name change to William Robertson took place on Wednesday 30 November 1960, at a meeting of Kesteven Education Committee in Sleaford.

It opened on 5 January 1961, with HORSA buildings. The first head was educated in Grantham, who was a flight lieutenant in the RAF during the war. It was officially opened on Tuesday 17 October 1961 by Brian Robertson, 1st Baron Robertson of Oakridge.

The school was to be three form entry. There were new buildings in the mid-1960s. The school was to cost £74,767. The deputy headteacher, Mr Padgett, became the first headteacher of the new secondary modern at Billinghay, in 1963. From September 1964 it worked with Grantham College to teach commercial subjects for one day a week.

It became a comprehensive around 1975.

• Farren Blackburn, film and TV director (1980–85)