Dr Boston, who was an architect of the original Gonski agreement and who also ran the British curriculum authority, rejected Labor's argument the bill should be voted down because it would deliver $22 billion less for schools over a decade than Bill Shorten has promised.
"The magnitude of what is within reach of being achieved far outweighs any other concern, including the argument that the present amount of funding is insufficient," he said.
"For the first time, the available funding would be distributed on a sector-blind needs-based principle, using a common assessment tool for individual schools nationally.
"When Labor next forms government, its promised additional $22 billion would have far greater impact when distributed on the basis of this new funding arrangement, than by being poured into the existing arrangement that has so debilitated Australian education."
Labor education spokeswoman Tanya Plibersek last week said the government's plan was "not needs-based" and "not sector-blind" and would leave needy schools under-funded for too long.
Dr Boston has previously criticised Labor's implementation of the Gonski Review, describing the deals with different states and school sectors as a "corruption" of the report's vision.
He has also described Julia Gillard's insistence that no school would be worse off under any changes as an "albatross" around the panel's neck.
Dr Boston acknowledged concerns about the government's model. The Catholic sector, for example, has complained about the reliance on socio-economic status data to assess parents' capacity to pay fees.
"In the main these matters arise from failure to implement the Gonski Report recommendation to establish a Commonwealth-state national schools resourcing body, which would have addressed them," he said.
"They can be dealt with readily, but only if there is genuine national commitment to treating individual independent, Catholic and public schools on the basis of equal access to sector-blind needs-based government funding, calculated using a common system for measuring need in all schools across the country."
With Labor opposed, the government would need the support of the Greens and one senator or 10 members of the 12-person Senate crossbench to pass its school funding changes into law.