Elizabeth Warren brought her Democratic presidential campaign to San Jose Friday, talking about the importance of her plan for universal, federally funded child care and higher pay for the people who work with those young children.

“We need to have high-quality care available for all our little ones,” the Massachusetts senator told a small group of child care providers at a family day care facility in San Jose. “If we want to meet the 21st century needs, the best place to spend money is on our children.”

Warren spent the morning with Rosa Carreño, who runs a child care business out of her home. The senator helped with some of the usual tasks at such centers, playing with the children, prepping for lunch, cleaning up and getting the children ready for their naps.

Warren wasn’t sporting a formal suit or dress like she would normally wear on the Senate floor or at a campaign debate. Instead, she had on black jeans, tennis shoes and a puffy coat, the type of clothes needed to keep up with the small children, both indoors and outdoors.

After helping with the kids, Warren held a half-hour discussion in the center’s tree-shaded backyard, against a background of colorful toys, child-size vehicles and paintings and pictures hung on a wood fence.

The visit reminded Warren, a former elementary school teacher turned college professor, “of what a gentle place an early childhood education center can be.”

It’s an experience that all children deserve to have, which is the reason behind her plan for universal child care and preschool, Warren said.

The senator wants to create a new federal child care system that would provide government-paid and staffed centers for babies and young children. In words on her website, the plan would “guarantee high-quality child care and early education for every child in America from birth to school age. It will be free for millions of American families and affordable for everyone.”

Warren described it as a supercharged version of Head Start, the long-running federal program that provides early childhood education to low-income children.

“Only it starts a lot (younger) and includes more,” she said, and will also be open to everyone, regardless of how much or how little the families make.

As many as 12 million children are expected to be part of the new child care program, according to Warren’s plan — nearly double the number of children who now receive formal child care outside their homes.

The plan isn’t cheap. An analysis by Moody’s Analytics suggested it could cost as much as $70 billion annually at full effect.

Warren acknowledged the cost, but said it would be covered by a new 2% levy on the nation’s wealthiest families, those with a net annual income of $50 million or more. It’s a way to ensure the richest Americans pay their fair share, she said.

“It’s a tax on the great fortunes ... on billionaires who own stocks, a Rembrandt and a yacht,” Warren said.

She said the tax would generate $2.75 trillion in new government revenue over the next 10 years. That’s enough money to not only cover her child care plan, but also such things as universal prekindergarten education, eliminating college debt, and providing child care workers, “mostly women and mostly black and brown,” with much higher wages.

“This treats workers more professionally and pays them better,” Warren said. In her version of the plan, the senator argues that “child care and preschool workers will be doing the educational work that teachers do, so they will be paid like comparable public school teachers.”

That pay hike, along with the increased number of workers that would be required under Warren’s plan, are reasons that the Service Employees International Union helped put together Friday’s event.

For Warren, though, boosting child care availability and making it affordable for every family is something that has to be done, regardless of the cost.

“If we shortchange the resources available, we make it so much harder on our children,” she said. “We’ve got to get a Washington that listens to people from a place like this.”

John Wildermuth is a San Francisco Chronicle staff writer. Email: jwildermuth@sfchronicle.com Twitter: @jfwildermuth