WATCH: White House press sec walks back 100 day school re-opening plan

A reporter asked Psaki, "Can you explain to American parents that just one day a week of in-person school, does that count as schools being open? Why should they be satisfied with that?"

"They shouldn't be. I wouldn't be as a parent. And I am a parent, I should say, I have two young kids. And I know many of you have kids as well.

"The President wants schools to open safely and in accordance with science, and we are going to listen to science and medical experts. The CDC guidelines, we expect them to come out tomorrow," she said.

"We are eager to hear more about the clear science-based guidelines for opening schools and how we can do that safely, and how we can keep them open. The president will not rest until every school is open five days a week. That is our goal. That is what we want to achieve.

"But we are going to, we look forward to seeing and hearing the CDC guidelines to gain a better understanding of what steps that will entail or should entail. The president's role of course is to ensure that across government we are listening to those guidelines, we are leaning into science, we are letting the science and medical experts lead.

"And that his objective is to ensure there's the funding to deliver on that. That's in the American Rescue Plan. So I can assure any parent listening that his objective, his commitment, is to ensuring schools are open five days a week.

"That's what he wants to achieve and we are going to lead with science and the advice that they are giving us, and the first step is tomorrow. The next step is tomorrow, I should say."

The CDC's Dr. Rochelle Walensky issued her understanding that schools were safe to reopen, but that has not yet resulted in the administration's understanding that schools should be open.

On Wednesday, Psaki said "Sure, his goal that he set is to have the majority of schools, so more than 50 percent, open by day 100 of his presidency. And that means some teaching in classrooms. So at least one a day week, hopefully it's more! And obviously it is as much as is safe in each school and local district."

The reporter asked for clarity, saying "When you say 'some teaching,' you didn't use the same majority qualifier there, you just said 'some teaching' in schools, some teachers in school, not the majority of teachers in school in the majority of classrooms."

"Teaching at least one day a week in the majority of schools by day 100," Psaki said.

"So that's in person teaching," the reporter asked.

"In person teaching," Psaki said.

Biden ran on a campaign promise of getting schools open within his first 100 days. If kids are treated to one day of in-person learning per week, that means that schools would be open only 20 percent, and not fully, which is what many parents were expecting. Many schools are already open at least one day per week, with some notable exceptions, like Chicago and Los Angeles.

Biden's plan to get schools open comes with a hefty $175 billion price tag, which he has put into his $1.9 trillion relief bill ask, under the American Rescue Plan.