Rising numbers of parents are lodging appeals after their children were denied places at a chosen school, with tens of thousands submitted last year, figures show.
In total, 54,600 cases were lodged for consideration in 2014/15, up 8% on the year before. More than a fifth of those heard by a panel were decided in favour of mothers and fathers.
The Department for Education (DfE) insisted that the proportion of appeals heard and upheld is stable amid increasing demand for places, and shows the system is working well.
Many areas of England, particularly major towns and cities, are facing an intense squeeze on places - particularly at primary school level - in part due to a rising birth rate.
A breakdown of the latest government statistics show that of the appeals submitted over entry to England's state schools last year, more were concerned with primary school places than secondary.
In total, there were 32,160 appeals over infant and primary schools, while 22,440 related to secondaries.
There was also an increase in cases heard, with 40,014 cases overall taken in front of an appeals panel - up from 36,967 in 2013/14.
More than 9,000 (22.8%) were decided in favour of parents, up marginally from 22.7% the year before.
The data covers both local council-run schools and academies, which are not under local authority control.
A DfE spokesman said: "The fact that the proportion of appeals heard and upheld remains stable in the face of rising demand for school places shows the admissions system is working well."
All parents have the right to appeal if a school they applied to refuses their child a place.
The current system allows parents to argue that schools broke official admissions rules or that there are "compelling" extra reasons why their son or daughter deserves a place.
Matt Richards, senior partner at schoolappeals.com, said: "With increased awareness through social and traditional media, coupled with improved and accessible guidance and professional support available to parents, those that are unhappy with the school offered to them are challenging the decision.
"Chances of success for those that prepare properly are also reasonable and an appeal is always well worth considering."
Figures published earlier this year showed that fewer youngsters got their first choice of secondary school this year, with around one in six missing out.
Overall, 84.2% of 11-year-olds got their top preference, according to DfE figures, meaning that around 15.8% did not. Last year, 85.2% got their first pick.
The figures also showed that 87.8% of children were offered their first choice of primary school, compared to 87.7% in 2014.