Democratic presidential candidate Bernie Sanders praised a decades-old Cuban national literacy program on “60 Minutes” this past weekend, drawing fierce criticism and renewing a long-standing debate over the quality of the country’s education system—and whether American policymakers should take lessons from any policy successes under an authoritarian government.

While Sanders criticized Cuba’s authoritarian regime, he also noted its large-scale literacy initiative in the 1960s.

“You know, when Castro came in office, you know what he did?” Sanders said of Cuba’s long-time leader. “He had a massive literacy program. Is that a bad thing, even if Fidel Castro did it?”

Cuba’s national literacy campaign, which trained more than 200,000 volunteer reading teachers to work across the country, did dramatically raise the literacy rate: Adult illiteracy rates fell from about 20 percent to around 4 percent in just one year.

Still, the initiative was the product of a totalitarian government that punished dissidents and silenced critics, and the lessons were designed to spread revolutionary ideology. Literacy teachers used government-provided materials that touted economic and social reforms and called for allegiance to Castro.

Soon after Sanders’ statement, the Vermont senator faced criticism from Republican and Democratic politicians, including other presidential candidates.

But in a CNN town hall on Monday, Sanders doubled down on his comments from the 60 Minutes interview. “I think teaching people to read and write is a good thing,” Sanders said, according to the AP. “That is a fact. End of discussion.”

In 2003, Education Week went to Cuba, to examine the successes and challenges of its K-12 system. In 2001, Cuban 3rd and 4th graders outscored children in all other Latin American countries in language and math, according to UNESCO research. Adult literacy rates held, too: In 2003, 96 percent of adults in the country could read, compared to 88 percent on average for all of Latin America and the Carribean.

Then-reporter Robert C. Johnston visited schools, teachers’ groups, and education officials, and found that the full picture was a more complicated story than the numbers alone could tell.

Here are three takeaways from his reporting:

The Cuban education system prioritized a strong focus on foundational literacy skills—and created structural supports for students and families.

How did Cuba maintain such high levels of reading proficiency? Marguarita Quintero López, then a teacher and the organizer of a biannual conference on pedagogy, told Johnston that “phonics-based teaching methods” were a strong contributor to student success. Students learned their letter sounds in kindergarten, and then the sounds for common letter groupings—known as phonemes—in 1st grade.

Cuban students were in school longer than most American children. The school day generally ran from 7:40 a.m. to 5 p.m., and school was in session 220 days a year (compared to 180 on average in the U.S.). The country also provided a universal outreach program for families with children under 5.

According to most recent numbers from the World Bank, Cuba spends 12.8 percent of its gross domestic product on education. The country doesn’t participate in the Programme for International Student Assessment, the international test of student achievement.

One aim of the education system: to “indoctrinate students in Communist ideology.”

The state controls education in Cuba, and teachers who go against party messages can face consequences. In 2003, teachers told Johnston that they had lost their jobs or been jailed for their opposition.

During Johnston’s reporting tour, members of the Association of Independent Teachers, a group opposed to the state monopoly over education, said that students could also be punished for refusing to follow party doctrine. Teenagers who didn’t join the Organization of José Martí Pioneers, a pro-revolutionary youth group, could be denied admission to universities, they said. (School officials denied this).

Johnston also saw how Cuban schools also purposefully combined work and study. In primary and secondary schools, students gardened, farmed, and cleaned as part of their academic day.

Teachers make low wages. They were (and still are) leaving the profession because of it.

In 2003, teachers made a monthly salary of about $15. Many were leaving the profession to take jobs as taxi drivers or in the tourism industry—options that could bring in a better paycheck. Students Johnston talked to weren’t interested in becoming teachers. They wanted “‘more possibilities’ than a teacher’s salary affords,” he wrote.

Teacher retention continues to be a major question for Cuban schools. At the beginning of the 2018-19 school year, the system was short 10,000 teachers, according to the country’s Minister of Education. Pay is still very low for educators in the country—the average monthly teacher salary was about $21 in 2018.

Image: Democratic presidential candidate Sen. Bernie Sanders, I-Vt., speaks during First in the South Dinner, Monday, Feb. 24, 2020, in Charleston, S.C. (AP Photo/Matt Rourke)