The QCA spent pound;30.92m on national tests for seven, 11 and 14-year-olds and baseline assessments for five-year-olds in 20012, the most recent figures show.
The total is 7 per cent up on 20001 and is 39 per cent of the authority's annual pound;79.2m budget, which includes a pound;68.7m grant from the Government.
Phil Willis, Liberal Democrat education spokesman, said: "You have to ask what is the benefit of spending this phenomenal amount of money on testing."
The figures represent the cost of administering, developing and monitoring tests for pupils under 14. In 20001, the bill was pound;28.91m. The costs of GCSEs, A-levels and vocational exams are largely covered by exam boards.
Ken Boston, QCA chief executive, said the total cost of all exams and tests could top pound;750m a year.
The accounts reveal that David Hargreaves, one of Dr Boston's predecessors, received pound;115,896 salary, bonus and benefits for 20012 despite resigning nine months into the year. His predecessor, Nicholas Tate, was paid pound;107,013 in salary and bonuses in 19992000.
The QCA paid pound;116,123 through an employment agency to Chris Walker, its temporary head of communications and knowledge management.
The annual pay of former QCA chairman, Sir William Stubbs, rose 37 per cent, from pound;51,247 to pound;70,625, in 20012. Sir William, who was sacked last year in the fall-out from the A-level regrading controversy, took over from Professor Hargreaves as acting chief executive in January 2002.
Overall, the budget rose 18 per cent to pound;79.2m. Staff costs rose from pound;15m to pound;17m, and the number of staff from 455 to 513.
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