Proceedings certainly have a mental age of about eight at the moment as Parliament squirms and fidgets over the Coalition's plan to put an extra $19 billion into schools and Labor arguing this means a $22 billion cut.

With the funding changes passing the lower house on Monday and awaiting a Senate response, the government and Labor cases can best be summed up as: "We give a Gonski" and "No, we give a Gonskier."

Maybe eight is being generous.

But, while MPs whinge and carry on about how the other side doesn't care about children and learning and the nation's future, something littler but just as important is being ignored.

The early childhood sector has been begging the government to do more for preschoolers for years now.

Currently, Australian children get 15 hours of preschool a week in the year before they go to school. This comes via a funding partnership between the federal government and the states, begun by the Gillard government and continued under the Coalition (Education Minister Simon Birmingham extended funding to 2018 in the May budget).

But education experts say this is not enough and funding is needed to ensure all three-year-olds get access to preschool as well. Only 66 per cent of three-year-olds are enrolled in some form of early education and care (some of which would include a preschool program). Almost all four-year-olds are enrolled in preschool.

This is not a routine call from a sector in search of money and relevance.

The Australian Early Development Census - a government initiative - measures Australian children in their first year of school across areas such as emotional maturity, cognitive skills and communication. According to the 2015 results, 22 per cent of children are "developmentally vulnerable" on at least one measure when they start school. If the child is Indigenous, this rises to 42 per cent.

At a national level, this is worrying as the government looks at ways of reversing Australia's slide in international education rankings.

At an individual level, this is potentially devastating. If a five-year-old starts kindergarten behind, they are more likely to stay behind for the rest of their school career. Victoria University education think tank, the Mitchell Institute, notes 28 per cent of Australian children start high school without basic literacy and numeracy skills.

Last year, Dr Stacey Fox, a Mitchell Institute policy fellow, co-authored a report arguing for two years of preschool.

"Early education is at least as important as school," Fox says.

"Research conclusively shows that high quality preschool programs benefit all children, and have transformative impacts for children experiencing vulnerability or disadvantage."

According to a 2013 Melbourne University study, the difference between no preschool and being taught by a diploma-qualified teacher was more than 30 points in mean year 3 NAPLAN reading and numeracy scores.

Long-term British research has found children who had two to three years of preschool had better language, numbers and concentration skills at the start of school. By the end, they had better English and maths results and took more final-year exams.

Whenever the concept of formal education for under-fives comes up, it can provoke scoffs about tiger parents and panickers - shouldn't kids be allowed to just scamper round and be kids?

But this is not about putting three-year-olds in uniforms and having them recite times tables and passages of Othello. Fox says preschool programs are about introducing children to the building blocks of literacy and numeracy, important social concepts such as co-operating and relationships, as well as learning to enjoy learning and discovering new things.

It's also about catching their little minds at a time when huge positive impacts can be made.

US economist Timothy Bartik says there is a "sweet spot" at ages three and four: "The child's brain is still malleable enough for modest interventions to have large long-run effects, but the child is old enough [to be] ready to learn in larger groups that are cost-effective to run."

There is a budgetary argument here. Bartik continues, "from a benefit-cost perspective, ages three and four offer the largest returns for a child's development per dollar spent".

So where is Parliament on this?

Birmingham has acknowledged the case for extending preschool to three-year-olds. But there is no move within government to do anything about this in the immediate future - school funding changes, university funding cuts and the introduction of the childcare package in 2018 are taking priority.

Labor's childcare spokesperson Kate Ellis gave a speech to the National Press Club last year singing the praises of more preschool at full volume. But the party's official policy is just for a review of the entire early childhood sector with a view to "serious reform".

So preschool campaigners can be quietly non-pessimistic about change some day. But this is not imminent nor guaranteed.

All of which is no use to children who are in the system (or not in the system) at the moment. As Early Childhood Australia chief executive Sam Page notes with frustration: "Three-year-olds are three years old now."

School funding - and who gets how much of all those extra billions - is of course terrifically important. But if the point is quality education for kids, we need to give a Gonskini too.