Every nursery in the country should have a qualified teacher to help children develop key skills like speech and language, a leading charity has said.
Thousands of youngsters are struggling to keep up with their peers as parents are unaware of the importance of pre-school development, Save The Children warned.
The charity said failure to properly stimulate toddlers' brains during nursery years could set them back for decades.
It has teamed up with leading scientists and psychologists to emphasise the importance of learning in pre-school years as a "critical opportunity" for the brain to develop key skills.
Last year almost 130,000 children in England were falling behind with language abilities before they even reached school, Save The Children said.
This means six children in every reception class struggled with their early language skills, it said.
It warned that failure to develop adequate language skills can leave children struggling to learn in the classroom and unable to catch up to their peers.
The charity said a new poll found that almost half of parents have low expectations for their child's early learning.
Of the 1,000 parents from England surveyed, 47% said they hoped their child would know 100 words by their third birthday - but this is only half of the recommended amount.
And 56% of parents do not think they have enough help and advice to understand their child's early learning.
The charity said every nursery should have a qualified early years teacher to support children and their parents with early learning.
"Toddler's brains are like sponges, absorbing knowledge and making new connections faster than any other time in life," said Save The Children's director of UK poverty Gareth Jenkins.
"We've got to challenge the misconception that learning can wait for school, as, if a child starts their first day at school behind, they tend to stay behind.
"To tackle the nation's education gap, we need a new national focus on early learning to give children the best start - not just increasing free childcare hours, but boosting nursery quality to help support children and parents with early learning."
Education and Childcare Minister Sam Gyimah said: "This Government is raising the bar and making a significant investment in the early years sector, working closely with the profession to help improve its status - and as a result salaries have increased, numbers of qualified staff have risen, the number of graduates in the workforce continues to rise, and a record number of providers are rated good or outstanding.
"We know that 80% of children are achieving the expected communication and language skills by age five - an increase of 8 percentage points since 2013. But we are determined to go further.
"That's why we provide funding for course fees and bursaries for eligible trainees, and are also supporting employers to help with their staff training costs.
"We are continuing to look at what more can be done to encourage talented staff to forge a career in the early years and this will be a key strand of our Workforce Strategy which will be published in 2016."
Neil Leitch, chief executive of the Pre-school Learning Alliance, said: "We welcome this report's focus on the importance of high-quality early years care and education, and in particular, the recognition that the idea that learning starts at school is an outdated misconception which should be challenged.
"As this research shows, the first five years of a child's life are crucial to their long-term learning and development, which is why it is so positive that - as demonstrated by recent Ofsted statistics - the quality of early years education in England is better than ever."
On the call for qualified teachers in every nursery, he added: "Research has shown that a graduate-led workforce can have a significant positive impact on children's early learning outcomes, and so we welcome any initiatives that support the sector to attract more graduate practitioners."