President-elect Joe Biden will ask Congress for $130 billion to help K-12 schools reopen, plus billions more to implement rapid coronavirus testing in schools, a far more aggressive response than anything lawmakers have approved to date.

Another plank of Biden’s proposal, announced Thursday, aims to mount a national vaccination plan that could facilitate school reopening as well, with vaccinated teachers more willing to return to classrooms.

The proposals are part of a $1.9 trillion “rescue plan” that also includes $1,400 stimulus checks to most households and other aid to state and local governments, transition officials said. A senior official called it a “bold and historic emergency package to change the course of the pandemic.”

For schools, Biden says his goal is to have a majority open for in-person classes within 100 days of his inauguration. It’s unclear how he will measure success, and some research suggests the nation may have achieved his goal.

The Trump administration has not kept track of how many schools or school districts are open for in-person classes, and a transition spokesman said the new administration will work to improve data collection.

Biden reiterated Thursday that he would do everything he could to safely reopen “a majority of our K through 8 schools” by the end of his first 100 days.

“We can do this if we give the school districts — the schools themselves, the communities, the states — the clear guidance they need as well as the resources they need that they can’t afford right now,” he said.

Biden hopes to achieve his goal with the help of a hefty federal aid package. At $130 billion, the K-12 schools piece of his proposal is more than twice the $64 billion provided to date over two previous relief packages. School advocates have complained that the dollars allocated so far fall far short of the need.

The K-12 funding is meant to address a wide range of needs. That includes expenses associated with mitigating virus spread inside buildings, such as improving ventilation systems, buying personal protective equipment and ensuring schools have nurses. It also addresses expenses associated with social distancing inside schools — reducing class sizes, modifying spaces and increasing the number of buses.

The package includes funding for mental health support for students and tutoring or summer school to help recover lost time in the classroom and learning. The money also could be used by states to prevent cuts to pre-K programs.

A portion of the funding would be reserved for an “educational equity challenge grant.” Details are not yet clear, but this suggests the Biden administration will try to use the new funding to advance equity goals, perhaps the way the Obama administration used stimulus funding in 2009 to advance its education change goals.

“It is absolutely imperative to have a package that focuses on both rescue and recovery,” said Randi Weingarten, president of the American Federation of Teachers. “I’m glad that the president-elect is putting forward a comprehensive package and someone is acting like a president.”

The outline of the package released Thursday did not specify how prescriptive Biden would like the funding to be. Under President Trump, states and school districts were given wide latitude in how they used federal aid.

The rescue package includes $35 billion in aid to public colleges and universities and to public and private historically Black colleges and universities as well as other minority-serving institutions. There does not appear to be dedicated funding for other private universities.

The plan arrived the same day the Education Department made $21.2 billion in stimulus funding available for colleges and universities to shore up their operations and support students through the pandemic. The latest round of congressional funding was met with disappointment from higher-education groups who pleaded with lawmakers for at least $120 billion in support.

Biden’s package also includes $50 billion to ramp up coronavirus testing nationally, including in schools. The hope is that by regularly testing students and educators, asymptomatic carriers of the virus can be identified early. A system of random testing is in place in New York City schools, but not many other districts have implemented that sort of system.

In addition, once Biden takes office, the Centers for Disease Control and Prevention is expected to issue a new set of guidelines for schools that better helps administrators safely operate in-person classes. For instance, districts have been asking for guidance on quarantining — who needs to quarantine after an exposure to someone who tests positive, and for how long.

Another key to reopening will be getting vaccinations to teachers, and Biden put mounting a national vaccination plan at the center of his rescue plan. The CDC has recommended that states include educators in the second-highest priority group, but the vaccine rollout has been inconsistent across the country.

“The one thing that’s going to help teachers more than anything is getting this vaccine out,” said Michael Osterholm, director of the Center for Infectious Disease Research at the University of Minnesota and a member of Biden’s covid-19 advisory board.

Biden has said his goal is to open a majority of schools within 100 days of taking office, but several experts in education policy said they had no idea how the incoming administration plans to measure that.

Some researchers have studied samples of districts, but no one has a definitive national picture of how many schools are open today. With school districts open throughout Texas and Florida and in many other communities, it’s possible the goal has been reached.

Khalilah Harris, managing director for K-12 education policy at the Center for American Progress, a liberal think tank, said Biden’s call was more of “a values statement” than an explicit measurement.

“I think it is a good goal, but I do not know how they plan to measure or track it,” said Michael Casserly, executive director of the Council of the Great City Schools, which represents urban school systems.

A transition spokesman said the federal government does not have tools to measure school reopenings and said the incoming administration is “working to enhance the federal government’s ability to effectively capture this data and assess progress toward safely reopening America’s schools.”

On Thursday, Biden clarified that his goal is limited to K-8 schools. Younger students have more trouble with remote learning and also are less likely to become infected with the coronavirus. It’s likely that hybrid systems, where students learn part-time from home and part-time from school, probably would count as open, said people familiar with the transition planning.

With the virus surging, it appears that districts are moving in the opposite direction. Many that were open have closed, according to a new analysis from the Center on Reinventing Public Education, which tracks a national sample of 477 school districts.

It found that in early November, 21 percent of school districts were operating fully remotely. By December, that had risen to 32 percent.

Still, the center’s data suggest three-quarters of districts had some form of in-person learning — well over a majority.

The Council of the Great City Schools keeps a tally of its members and found 18 districts closed after having reopened this fall. Another 28 school systems are open now, the group said, including Chicago Public Schools, which opened this week even as many teachers refused to return to their classrooms, citing safety concerns.

Erica Werner and Danielle Douglas-Gabriel contributed to this report.