As the President-elect determines the priorities for his first 100 days in office, he should focus on children’s first 1,000 days of life. Recent breakthroughs in neuroscience have revealed that children’s brains are growing explosively during the first three years of life – developing more than 1,000 trillion synaptic connections. This is also the moment in our lives when we are most vulnerable to trauma. Investments in basic supports early in life reap enormous benefits later on.

Children who are exposed to traumatic experiences like neglect, abuse, homelessness or parental depression have their brains rewired by this toxic stress. This stress impacts the development of language, memory and self-control. These foundational experiences organize the brain to respond to the world accordingly. Early experiences that are very stressful or unpredictable inhibit an infant’s ability to learn and form trusting relationships. By 24 months, many toddlers living in poverty already show both behavioural and cognitive delays.

Missing this small but vital window of opportunity leads to the need for intense – and all too often failing – efforts in our schools to ensure all children have equal opportunities to succeed. Most of the achievement gap between rich and poor children is already evident by kindergarten, and it stubbornly persists as children enter and complete middle and high school.

Compounding matters, educational systems across the country are poorly positioned to manage this reality – like a football team that doesn’t compete in the first quarter of every game they play. Nationally, we spend close to $600 billion a year on K-12 education, while only allocating roughly $20 billion to childcare and educational supports before children start school. On a per capita basis, we spend roughly 10 times less on education for our youngest children at exactly the moment when the potential impact is greatest. You can find the opposite pattern in every other wealthy nation in the world.

As on other issues, Americans are ahead of their elected leaders. Even during an election filled with talk of debt-free college, twice as many US adults prioritized early childhood funding over post-secondary funding and more than two-thirds support the idea of providing free childcare and pre-kindergarten programmes for all children.

There are a number of promising policy ideas that can help our children get a strong start in life so they can succeed in school and careers as they grow older. All learning occurs within the context of relationships, so we need to ensure the presence of significant adults in babies’ lives, adults who are able and ready to build supportive relationships. Those relationships suffer if the adults are stressed and don’t have the emotional, psychological, or financial resources to care for a child.

Building relationships starts at birth with policies and practices that support parents (ideally both mothers and fathers) staying home with the new baby for as long as possible. During the presidential campaign, both candidates put forth plans to guarantee paid maternity leave – this is a start.

For new parents, we must provide more supports. Home-visiting programmes, like the Nurse-Family Partnership, model strong parenting through home visits aimed at building healthy attachment between children and first-time parents, offering opportunities for early literacy and identifying children with special needs. Healthy Steps is another innovative approach that takes advantage of pediatric care visits to teach parents similar skills. Publicly supported parent-child play groups led by educators are another cost-effective way to offer families a chance to socialize, build support networks, and learn about their child’s developmental needs.

Investing in programmes like these will help parents better support young children, but – following the lead of every other developed nation in the world – we also need to build a serious infrastructure that acknowledges the reality that most parents work and their young children will be cared for by others. After all, this precious time in life is when the quality of the caregiver matters most.

Therefore it is incumbent upon us to make sure caregivers are prepared to provide high-quality childcare. Quality is a problem that cuts across all income levels. Very few of our programmes are high quality – studies put the number at 1 in 10. This places all our children gravely at risk. Research links low-quality childcare to toxic stress and developmental damage. When an infant spends a year with someone who is not able to form a relationship with him, it will have an impact on behaviour, learning, and potential for years to come.

The antiquated idea that “anyone can take care of babies” is part of the problem and leads to a lack of funding, low wages, and low-quality childcare. There is a big difference between meeting the child’s feeding, diapering and sleeping needs, and providing care that will nourish the child’s mind and body. In quality childcare settings, a child is free to explore and, importantly, come back to her caregiver when she needs to “refuel” to continue her learning. The caregiver comments on the child’s exploration, signifying that what she does is important and modeling language that is connected to the child’s interests. High-quality childcare starts with strong, nurturing relationships that are stable and offer children a secure base from which to engage in new experiences within a thoughtfully planned routine. To achieve this level of care, we need to develop a strong public infrastructure for childcare, with mandatory training for all caregivers written into licensing rules at the state level.

We now know the precise time when our children’s brains are most responsive to support and care, and when parents are most in need of support, and as a nation we’re ignoring it. If we are serious about equity and if we truly care about our children, we need to move quickly to address these gaps for the youngest and most vulnerable members of our society.