Under the London schools admissions system, to be launched this September, parents will list six schools in any of the 41 LEAs taking part in order of preference. They will then receive one offer on March 1, 2005 for the school which is closest to the top of their list.
The pound;1.5 million Government-funded system is designed to stop some parents being offered several secondary school places while others are offered none.
Speaking at the official launch of the new system, Mr Twigg said the computer-generated system could provide "some lessons for other urban areas in the country".
He said the new system was needed because the Education Act 2002 - which requires all LEAs to co-ordinate admissions to their secondary schools from 2005 - did not go anywhere near meeting London's admissions problems.
"From visiting primary schools and talking to Year 6 pupils, time after time I am meeting children who have two or three places and next to them there is another child with no offers. It is not acceptable to have that position. This will make a big difference."
All of London's 33 boroughs are taking in the scheme, as well as neighbouring councils Buckinghamshire, Essex, Hertfordshire, Kent, Slough, Thurrock, Surrey and Windsor and Maidenhead.
Stephen Beck, headteacher at St James the Great RC primary and nursery, Croydon, south London, said: "Parents will hold as many as five or six places which disadvantages other parents who are left with no offers.
"Parents come to me very distressed. They are not only not getting the school they asked for, but no school at all."
In September the London schools admissions system's executive board will consider whether an internet portal allowing London parents to access information on all schools taking part in the project is feasible. Parents would also be able to submit applications online.