Local councils in England say increasing numbers of parents have been caught trying to cheat to get places for their children at popular schools.
Competition for places in top schools is intense
They say there is a "worrying trend" of people lying about where they live - breaking the law in doing so.
Out of 31 councils surveyed for the Local Government Association, 24 said they had seen an increase in cheating.
Cases detected in 2007/08 were nine times higher than two years ago according to the LGA.
They were nearly three times higher than last year.
Areas which reported increases over the past three years include Richmond Upon Thames (up from 5 to 50), Cheshire (up from 0 to 16) and Coventry (up from 0 to 14).
Councillor Les Lawrence, chairman of the Children and Young People Board of the LGA, said: "There appears to be an emerging and worrying trend of parents willing to break the law in order to try and get their children into the best schools.
"While everyone wants the best for their children, parents who are willing to go beyond the law means that other law-abiding parents and children miss out.
"Councils work extremely hard to ensure that every child has a fair chance of getting into their parents' preferred school. Unfortunately, many high-performing schools are oversubscribed and therefore attract fraudulent applications."
Increase in cheating in past three years
Richmond Upon Thames: up from 5 to 50
Cheshire: up from 0 to 16
Coventry: up from 0 to 14
Bristol: up from 2 to 8
Trafford: up from 0 to 6
Poole up from 0 to 5
Gloucestershire: up from 0 to 4
Parents who use false addresses are breaking the law under the Fraud Act 2006, the LGA says.
In most cases the offer of a place is withdrawn but parents are not prosecuted.
The association says common examples are of parents giving the address of a relative within the catchment area of a good school or renting a home in the area but then renting it out to someone else.
Councils usually ask for applications to be accompanied by proof of address such as a mortgage statement, utility bill or child benefit document.
The LGA says cross-checks are made with council tax and electoral records, if necessary, but that many bogus applications come to light after other parents inform the council.
Councillor Malcolm Eady, from Richmond Council, said: “We have seen a big increase in the number of bogus applications for primary places from around a handful in 2006-07 to approximately 50 this year.
"We have the best primary schools in the country and they are therefore extremely popular.
"The most common examples we uncover are: parents stating the address of the child's grandparents as being the child's home; parents stating the address of a property which they own but are renting out to other people; and parents who own more than one property not giving their correct home address.
"Our admissions team knows every trick in the book and are successful in rooting out bogus applications.
"We work extremely hard to find places for every child and make the system transparent and equal for all. We are therefore appealing to parents to play fair and stick to the rules."
It is not clear, the LGA admits, whether it is the case that the numbers of people attempting to cheat the system are rising or that the councils are getting better at spotting bogus applications.