Gillard said that despite the site, which is to launch on Friday, showing wide disparities in funding between Catholic, independent and public schools, the information provided on the second version of the site would improve education.

"I didn't want the debate in education in this country to be about what people might think is the case," she said. "I didn't want it based on assumptions, I wanted it based on accurate information.

"I wanted people to see through My School what the amount of money to each educated child was."

Gillard said the site would offer parents information not previously available on the funding level of each individual school regardless of its type.

"We need information at the school level and we would never have had this information before," she said. "Now, I can't tell you in a year what information it will show, what assumptions people have made about education, what it is going to prove true and what assumptions it is going to smash to the ground.