PARIS — France pushed forward with the reopening of schools on Tuesday, sending more than 12 million students back for mandatory in-person classes, even after the country reported a sharp rise in new coronavirus cases.

Government officials have warned about a possible need for a second national lockdown, and some schools in highly affected regions will remain closed. But the government wants most students in their classrooms, to facilitate the return of parents to work and to curb a learning gap between high- and low-income students that authorities believe worsened during the two-month lockdown in the spring.

“Not everything should be destroyed by the health situation,” Education Minister Jean-Michel Blanquer told France’s Journal du Dimanche newspaper. “We must be vigilant, but not forget the educational and social imperatives, nor deviate from our two objectives: improving the educational level of each child and reducing inequalities.”

Despite the recent increase in cases, 79 percent of French parents were in favor of sending their children back to school Sept. 1, according to a recent survey by France’s Ifop polling agency.

Crowds of parents and students gathered outside schools on Tuesday morning, with many students visibly eager to return to in-person learning. In central Paris, the sounds of the recess hour at certain schools could be heard blocks away.

Some teachers and health professionals, though, have criticized the government’s plans. While there has been little evidence of school-based transmission in Europe or around the world, school outbreaks in Israel and Chile have caused concerns about schools accelerating community spread.

“We’ve always known that was a likely outcome, but we don’t think the Education Ministry is very well prepared,” said Sophie Vénétitay, the general secretary of one of France’s largest teachers unions.

Writing in Le Parisien on Saturday, a group of medical professionals argued for requiring masks for all students age 6 and older — instead of the government’s guideline that applies to only those 11 and older. The doctors also advocated more-robust air-ventilation measures and efforts to reduce contact between children in different classes.

The government defends its policies, which it says are in line with the recommendations of France’s public health authorities.

Social distancing guidelines have been relaxed since French schools were last in session. To accommodate full classes, an initial requirement of four square meters between students was reduced to one meter laterally and then dropped altogether for the fall. Now, teachers have been asked to set up classrooms with “as much distance as possible” between students, while “social distancing no longer applies” outside.

School sports will go on, in line with public health protocols, and although large indoor spaces such as gyms are to be avoided, school cafeterias will still serve meals.

Blanquer was recently asked whether parents should consider not registering their children for school meals this year. His answer was an adamant no.

“The cafeteria is a social issue — one of sociability, of civility,” he told the Journal du Dimanche. “It’s one of the things where we have to say, ‘Life goes on, despite the epidemic.’ It’s up to us, the French, to prove our ability to rebound, like a body defending itself against the virus. Otherwise, we close everything and stay home. It’s the easiest, but it’s not good for children.”

The government recommends that cafeterias serve smaller groups at different times.

France has seen a rapid rise in confirmed cases of the coronavirus. New infections surged by nearly 50 percent in August, making for the highest monthly tally since the beginning of the pandemic, Reuters reported.

On Tuesday, France reported 4,982 new cases from the previous 24 hours.

Fewer cases in France are requiring hospitalization than in the spring, and mortality is nowhere near the spring peak. Health experts say that’s in part because young adults make up a higher proportion of those testing positive and typically aren’t hit as hard as the elderly.

France’s school reopening plans do not apply to universities, which are also resuming classes but are striving to move as much teaching online as possible for the academic year.

Prime Minister Jean Castex announced last week that plans for a second lockdown had been prepared, although he said that would be a last-resort option. The government is concerned about subjecting the French economy to another devastating blow.

The government’s resolve in reopening schools reflects economic calculations, too. President Emmanuel Macron has also expressed repeated concern about the learning gaps that lower-income students in particular will face after the months of lockdown earlier this year. And France’s Education Ministry has referred to the issue in its defense of the government’s current plans.

Teachers say they share Macron’s concerns and that helping students who may have fallen behind catch up is among the most significant challenges they will face this school year. But for many, the issue of health risks that remain is impossible to overlook.

Guislaine David, secretary general of a major grade-school teachers union, said starting the year with certain schools already closed was an ominous sign, and that other school closures were bound to follow.

“It’s almost certain,” she said.