Changes this year include new indicators of pupils' progress
The tables show the results achieved by schools in the Key Stage 2 national curriculum tests in England in 2009.
Those are the tests pupils are required to sit in the final year of primary school, at the age of 10 or 11.
The results are published by the Department for Children, Schools and Families.
They include "contextual value added" (CVA) scores - produced by the department to show how much a school has improved its pupils' achievements since they took their first set of assessments in 2005.
And this year there are new "progress measures" giving another view of how pupils' attainment has improved.
The figures relate to all local authority-maintained mainstream primary and middle schools with pupils eligible for assessment at the time of the tests in English, maths and science in May.
They do not include special schools, pupil referral units, hospital schools or private schools.
What is in the rankings
The schools are listed within each local authority (LA) in two ways: Alphabetically and ranked on the combined or "aggregate" score achieved in the three tests - the maximum possible being 300.
In the rankings, where more than one school has the same score, they are further ranked on the average points scored by pupils (see below for more on how this is calculated).
In the alphabetical LA lists, after the school's name, the first column of figures shows its CVA score, then the aggregate score - and the results can be sorted on that column - as well as the average number of points achieved by pupils.
The results relate to the percentage of the pupils eligible to take the tests who achieved Level 4 or above - the standard expected for their age.
A CVA score is worked out for each pupil by comparing their Key Stage 2 performance with the middle performance of other pupils with similar prior attainment at Key Stage 1.
The arithmetic mean of these individual scores gives a score for the whole school. This is converted to a number based around 100.
Note: the resulting rankings need treating with care. Official statisticians say the significance that can be attached to different scores depends on various factors, including the numbers of children involved.
For various reasons complete "before and after" scores are not available for all pupils. Where the data are missing for 50% or more of those eligible to take the tests, the value added score is not published.
The aggregate (AGG) score is a number out of 300 but is not simply the sum of the percentages of pupils achieving the expected level in each subject. It is derived from the number of pupils achieving at least the expected level, divided by the number eligible to take the test, for each subject, added together and multiplied by 100.
The letters SS signify a small school - with fewer than 11 pupils eligible to take the tests. They are included in the alphabetical lists for completeness but no results are published for them so they do not appear in the rankings.
Once the tables have been fully published on 2 December, clicking the name of any school in any of the lists takes you to its individual page.
As well as basic information about the school, its RANKING among others in the area can be accessed via a link at the top of the page.
Under PERFORMANCE is the figure for the number of pupils eligible to take the tests and, next to that, the proportion of those deemed to have special educational needs (SEN) - with or without formal statements.
There is then a trend measure, showing the combined or "aggregate" scores for this year and the previous three years, along with local and national averages - all illustrated by at-a-glance comparison bars on a scale from zero to the maximum of 300.
An NA means the results are not available for some reason, such as the school had too few pupils (10 or fewer) for its results to be reported in the relevant year, or was not open at the time.
Then the separate results for each subject, ENGLISH, MATHS and SCIENCE are reported, again with comparison bars - the scale being zero to 100%.
The "Absent or unable to access the test" figures alongside refer to those who were not there to take the test for whatever reason, and to the few pupils who were not able to take part, usually because they had certain special educational needs.
Then there is a line summarising the percentage of pupils who attained Level 4 in both English and maths - one of the targets schools have.
The AVERAGE POINT SCORE bars show how well this school did compared with the worst and best in the country (the range being 15 to 32.9 points) and the local and national averages.
The average point score is designed better to reflect the achievement of all pupils, not only those reaching Level 4. It involves adding up all the points pupils achieved in the three subjects, then dividing this by the number of pupils eligible to take the tests.
Under PUPILS' IMPROVEMENT are two ways of showing progress:
The CONTEXTUAL VALUE ADDED score. The red bar allows you to see at a glance how well this school did, compared with the worst and best in the country, the range in 2009 being 94.7 to 105.
The PROGRESS MEASURE for English and maths, new in 2009, shows the proportion of pupils whose attainment rose by at least two national curriculum levels between the end of Key Stage 1 (aged about seven) and the end of Key Stage 2 (10 or 11).
All pupils who attained Level 5 in their tests are treated as if they had made the expected progress, as this is the highest level at which they are assessed.
Then there are ABSENCE figures showing the percentage of half-day sessions lost due to total absence and what percentage of pupils are persistent absentees - meaning typically they missed a fifth of lessons, with or without permission.
A "negligible" absence return means more than 0 but less than 0.5%.
There is a link to the official Profile completed by the school itself in a government template.
Types of school
Community - maintained by the local education authority (LEA), which is responsible for admissions arrangements.
Voluntary aided - maintained by the LEA, with a foundation (generally religious), which appoints most of the governing body, which deals with admissions.
Voluntary controlled - maintained by the LEA, with a foundation (generally religious), which appoints some - but not most - of the governing body. The LEA is the admissions authority.
Foundation - maintained by the LEA. Some may have a foundation (generally religious), which appoints some - but not most - of the governing body, which is the admissions authority.
Academy - independent state schools where sponsors invest in the building or modernisation of the premises and the state meets running costs.
Ministers agree it is unfair for schools to be judged on the results of children who have arrived recently from overseas and whose first language is not English, so the schools can choose to omit these pupils from the eligible number in the performance tables.
Some schools will have improved their performance as a result, although they are not identified in the data.
This change is also reflected in their local education authorities' averages - but not in the national averages.