Bolsonaro and top officials have announced plans to revise textbooks to excise references to feminism, homosexuality and violence against women, say the military will take over some public schools and frequently bash Paulo Freire, one of Brazil's most famous educators, whose ideas had worldwide influence.
"One of the goals to get Brazil out of the worst positions in international education rankings is to combat the Marxist rubbish that has spread in educational institutions," Bolsonaro tweeted on the eve of his inauguration.
While students may not yet find many differences as they return to school this month, changes are afoot.
"We are still waiting to see how, in practice, all this is going to turn out," said Nilton Brandao, president of one of Brazil's largest teachers' unions, PROIFES Federacao. "Right now, it does not make any sense."
For the government, the ideological battle begins with the removal of Freire's legacy in schools, which Bolsonaro and other conservatives say turns students into "political militants."
Freire, who died in 1997, was one of the founders of critical pedagogy. Conservatives contend Freire's method encourages students to challenge traditional values such as family and the church. A socialist, Freire was briefly imprisoned during the 1964-1985 military dictatorship that Bolsonaro has repeatedly praised.
On the campaign trail, Bolsonaro said he wanted to "enter the Education Ministry with a flamethrower to remove Paulo Freire."
Bolsonaro and his education minster appear to be looking for inspiration in philosophers like Olavo de Carvalho, a Brazilian who lives in the U.S. and is known for his anti-globalism and anti-socialist views.
While Freire believed in the state's mission to educate the Brazilian people, including poor rural farmers and the illiterate, de Carvalho advocates reducing the state's role in education, favoring private or religious schools.
"The government does not have to educate anyone; it is the society that has to educate itself," de Carvalho said last year during a talk about education on his YouTube channel. He added that proposals "based on the idea that the federal government is the great educator I am going to fight to the death."
After Bolsonaro took office Jan. 1, the Education Ministry dismantled its diversity department and published a new set of guidelines for textbook publishers that eliminated references to topics such as violence against women and sexism.
Receiving an outpouring of criticism, officials backtracked on the revised texts, saying the new guidelines had been written by the previous administration and published by mistake. Even so, Education Minister Ricardo Velez Rodriguez vowed in his inaugural speech to end the "aggressive promotion of the gender ideology."
Velez instead defended what he called traditional values, such as family, church, school and the nation, which he said were threatened by a "crazy globalist wave."
"The Brazilian who travels is a cannibal. He steals things from the hotel, steals the life jacket from the plane," said Velez in an interview with Veja magazine this week. "Our kids and teenagers must receive citizenship education, which teaches how to act according to the law and morality."
Bolsonaro has said he would review the content of Brazil's national high school exam to rid it of any questions on gender or LGBT movements. He made the announcement in a YouTube video after seeing a question from last year's exam on a "secret dialect used by gays and transvestites," called Pajuba.
The Pajuba dialect mixes Portuguese and West African languages and is mostly used in Afro-Brazilian religions but has also been adopted by the Brazilian LGBT community.
"Don't worry, there won't be any more questions like this," Bolsonaro said.
After his inauguration, Velez told the newspaper Folha de S. Paulo that his office will encourage municipalities interested in letting their schools be run by the military or the police.
Brazil has 13 military-run schools, which are aimed at educating children of soldiers but also accept some students based on merit. The military is the most respected institution in the country and its schools have a better reputation than many public schools.
The military is also sometimes called in to co-run public schools and bring back order.
Last year, 39.5 million students attended a public school, while private institutions, which can cost several thousand dollars a month, served 9 million.
Opponents say the selective admission process of military schools would end up being discriminatory in impoverished areas.
In general, critics say the administration is focused on the wrong things.
Claudia Costin, director of Brazil's Center for Excellence and Innovation in Education Policies, a think tank based in Rio de Janeiro, said efforts should focus on improving training and salaries for teachers, making the entrance exam for teachers tougher and building a common syllabus for schools across the country.
The government "complains about indoctrination at school," Costin said. "But it is not with laws that you solve these things."
Brazil ranked 63rd out of the 72 countries and regions in the 2015 Program for International Student Assessment, conducted by the Organization for Economic Cooperation and Development.
According to the group, Brazil has as one of the largest shares of adults without secondary education. Schools are overcrowded, teacher salaries and low and school buildings are often crumbling.
More than 5.800 schools had no water supply in 2017, nearly 5.000 had no electricity and 8.400 had no sewage, according to government figures.
Many Brazilians don't appear convinced by Bolsonaro's plans.
In a poll published Jan. 8, 71 percent of those surveyed said politics should be discussed at school and 54 percent thought it was fine to discuss sexual education inside the classroom.
The poll, however, indicated that the new administration's conservative views played well with evangelicals, a powerful voter base for Bolsonaro during the campaign. Fifty-nine percent of evangelicals said they did not approve of sexual education being discussed at school.
The Datafolha poll was based on 2,077 interviews carried out Dec. 18 and Dec. 19, with a margin of error of two percentage points.
Caua dos Santos Borges, a 15-year-old public school student in Rio de Janeiro, said that in her experience teachers rarely spoke about politics in the classroom and gender had never felt like a core area of the curriculum.
"Once, a student asked the teacher if he supported Bolsonaro, but the teacher didn't respond and changed the subject," dos Santos Borges said.
Diane Jeantet on Twitter: twitter.com/dianejeantet