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The information required is not held in the format requested. The data provided reflects only the category of 'State' schools (noting that for the purposes of Combined Cadet Force (CCF) data collated by MOD, all other schools are categorised as Independent).
As at 1 April 2009, and subject to the caveats mentioned above, there were 7,579 School pupils who were members of their State School's Combined Cadet Force. However, given that the majority of Cadets are members of a community-based Cadet unit, it is estimated that some 90,000 cadets are state school pupils. In the same timeframe there were some 130,000 cadets overall. It should also be noted that there are 25 known partnerships where Independent Schools with CCFs provide cadet places to neighbouring State schools; for these partnerships it is not possible to identify the numbers of State School cadets.
Full statistics on cadet forces can be found on the Defence Analytical Services and Advice organisation's website in their Tri-Service Publication (TSP) 7: