Bluntly, with great difficulty. You must try to decrease the chance of such absurdly high test results. Here are some suggestions.
The first takes a little explaining. Arrange a series of meetings on Helping your Child obtain the Best from their Schooling. Invite Responsible Parents of two to four-year-olds in your catchment area. Your main target is the nearest you have to a middle-class group. The others probably will not come anyway. Magazines and "intelligent" TV programmes urge parents to share books with their children, to explore counting with their toddlers and so on. You must counteract these influences. If not, tiresomely excellent baseline results will leave insufficient "scope" for your superb key stage 1 and 2 3Rs programme.
At your meetings cultivate a grave professionalism about early reading and number. Intimate that there are both Good and Bad methods. Many parents do so much before school age to help their children, but some may unwittingly encourage inappropriate developments. Mention the old fear that reception children will be terminally bored if already reading when they come to school. Help earnest parents to realise that the school should be left to handle the beginnings of reading, writing and number.
For instance bad letter formation is hard to remedy. Three and four-year-olds writing their names are already acquiring habits . . . Consider talking slight]y confusingly about the importance of learning letter names and sounds correctly. Should children learn letter names first, or sounds? What about lower and upper case letters? Wonder aloud whether learning these in the wrong order hinders progress. There's the new emphasis on phonics, and the potential damage of an inappropriate "real books" approach. Can a misinformed parent with the best intentions help to cause reading failure? Many do not feel confident in mathematics. Vaguely express worries about whether those not wholly confident and competent mathematically should be helping pre-school children with number.
By the way, who is actually carrying out the tests? Why not a teacher with an unfamiliar dialect and accent? She might be the kind of person who from time to time uses long words and complicated sentences. Can you arrange matters so that an intimidating colleague is in charge? Indicate that it would be unprofessional to provide the children with positive feedback while they are put through their paces.
Do make sure that the children are assessed towards the end of the day. Before the big event, subject them to some exhausting activities. Outside PE might well be the answer. If you can, go for a heat wave.
Failing all this, don't take middle-class children. But be careful! There are still those KS 2 test results to worry about.
Of course, if all schools follow this guidance they all return to a level playing field. You may feel that this is a frightful waste of time, but you simply cannot afford to be the one not acting on the best advice. You must excel at depressing your baseline scores, otherwise, what hope have you of coming out well in the "added value" tables?
Everything changes once the children have taken the tests. It is immediately the Duty of the Responsible Parent to support reading and number. If your earlier confusions have been sufficiently subtle, only the sharpest parent would detect any conflict between your current and past messages.
Dr Andrew Davis is lecturer in education at Durham University.