It's good news for parents as politicians seek the 'family' vote in the upcoming federal election, and on the table is long overdue universally funded preschool for three-year-olds.

Until now, in Australia only four-year-olds have been guaranteed a place in preschool. However the evidence is mounting globally that two years of preschool gives children the best start.

However in Australia only parents willing to pay for it can currently access preschool for their three-year-olds, putting us behind much of the developed world.

In the NSW state budget announcement in June, it was announced that NSW would be stepping up to the plate as the first state government to expand preschool subsidies to three-year-olds, saving families about $825 a year from January, 2019.

Today, opposition leader Bill Shorten will pledge that if Labor wins the next federal election, about 700,000 three and four-year-old children, nationally, would be guaranteed 15 hours a week of funded preschool or kindergarten.

Under the proposed $1.75 billion plan, preschool would be extended to three-year-olds, giving children 600 hours of subsidised early childhood education a year, bringing Australia in line with the rest of the world when it comes to funded early education.

"All the research, science and experts make it clear the more early years learning we can give our kids before they go to school, it just absolutely quantum improves their learning experience at schools," Mr Shorten told the Nine Network.

The UK, France, China, New Zealand Germany and Norway, have long been providing universal preschool for three and four year olds. East Asian countries renowned for consistently topping education performance lists are moving towards universal access for three and four year olds too, so it's definitely time for Australia to step up.

"Some of the smartest countries in the world are doing it. Australia has fallen behind," Mr Shorten said.

Dr Stacey Fox, key researcher at Victoria University into three-year-old preschool is an advocate for two years of early childhood education for all Australian children.

"It means children are much more ready when they start school, they start school on a much more equal footing, it has flow on impacts to their NAPLAN scores, to their rates of Year 12 graduation," she told the ABC.

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Why is three-year-old preschool so important?

In article penned for [The Conversation]( |target="_blank"|rel="nofollow"), Dr Fox explains why preschool is so important.

"Preschool programs (also known as kindergarten) provide an environment for children to develop their skills, capabilities, interests and talents. Preschool is about helping children learn to get along with others, to be creative and collaborative problem solvers, to understand and talk about their emotions, as well as supporting the foundations of literacy, numeracy and science," she writes.

"Preschool has benefits for all children, but the biggest impacts are seen with the children who need extra support the most – the 23 percent of children arriving at school developmentally vulnerable. Evidence shows that one year of preschool isn't usually enough for these children to catch up."

Labor has deemed that this is a good investment for families, and Australia.

"We are able to do it because we're winding back some of the unaffordable tax concessions at the top end which we currently pay to some Australians," Mr Shorten said.