Bristol pupils have achieved one of the worst sets of GCSE results in England.
The national target was 38% getting five GCSEs above grade C
League tables out on Thursday show a third of pupils achieved at least five A* to C grades in 2004 - the second worst percentage in the country.
The next worst performer in the west of England was South Gloucestershire, where half of all pupils scooped five A* to C grades.
The average points score per 15-year-old in Bristol was nearly 264 - the worst performance in England.
The best average points-per-pupil score was 471.3, in the Scilly Isles.
The national government target was for 38% to achieve five GCSEs above grade C.
Heather Tomlinson, director of education and lifelong learning at Bristol City Council, told the BBC: "The results last year were clearly very disappointing and the standards achieved are not acceptable for a city like Bristol.
"But everyone has worked hard to do their best and the question we've been addressing with our schools is 'are we doing the things that are making the most difference'?
"Over time, perhaps we have been trying to do too many things [last year], running too many initiatives.
"This year we have agreed to focus back on the basics, consistently across the city. I think that will make a huge difference.
"We will achieve success here in Bristol."
The council says it has several key priorities for education in the city next year, including:
raising attainment at 5+ A* to C GCSE grades by 5%
every pupil targeted to attain at least one A* to G score
raising levels of literacy, attendance and participation
widening curriculum choice for 14- to 16-year-olds
Two high-profile initiatives already under way are aimed at tackling truancy and rebuilding secondary schools.
Plans to build in "structured support" programmes at schools to target pupils vulnerable to not achieving core GCSEs are also on the table.
And the council will use a new electronic system of data collection to track pupils' progress; push extra resources into literacy and develop an out-of-school support service.