CANBERRA, May 11 - Legislation for its single needs-based model and increased funding of $18.2 billion over the next decade will be introduced to parliament on Thursday.

It will include a three per cent floor to the annual indexation of the base funding amount known as the student resource standard.

That base indexation amount is contained in existing legislation.

However, Treasury projections indicate the base amount will grow faster than this once fixed indexation ends in 2021, the government says.

"We want to make sure that there is no question around the certainty that our model can give all Australian schools to plan for the next decade and beyond," Education Minister Simon Birmingham said.

"I am committed to stopping the school funding wars and I urge all parties to end their scare tactics and stop their campaigns for special treatment."

The Catholic sector has been up in arms over the funding changes, which it says will lead to massive fee increases and possibly school closures.

Treasury figures show the SRS should grow by 3.3 per cent a year beyond 2021, meaning funding to Catholic schools will grow by an average 3.5 per cent over the decade once the needs of their students are taken into account.

Senator Birmingham said schools should be confident that if wages growth ticks up, the government's funding model would keep up.