HAVANA -- "This is a conversation between two children," Graciela Lage Delgado tells a rapt class of third-graders, tightly enunciating each English word from a textbook called "Welcome to America."
"Is it a TV?" Lage asks in a girl's voice, pointing to an illustration of a boxy silver robot.
"No, it's not!" the kids shout back in English. "It's a robot!"
Lage's class has an air conditioner and a computer with speakers for watching videos, unimaginable in a Cuban state school. And unlike most Cubans their age, the children can hold simple conversations in English, thanks to fast-moving, profound change in an important pillar of Cuba's six-decade-old socialist system.
Cuba touts its free, public kindergarten-to-post-grad schools as one of the jewels of its revolution, a force for social equality that virtually wiped out illiteracy across the island and gave even the poorest citizens a shot at educations often superior to wealthier countries'.
As the government has allowed an explosion of private businesses ranging from restaurants to car washes, the school system, like health care, has remained under state control. Private schools remain illegal except for children of diplomats and foreign business people. Even the Catholic Church cannot open parochial schools.
Yet against the odds, Cuba's blooming entrepreneurial system has quietly created something that looks much like a private education sector, with thousands of students across Cuba enrolled in dozens of after-school and weekend foreign language and art schools. The schools are entirely legal because they function as cooperatives of licensed private language teachers, one of the hundreds of new categories of self-employment authorized under Cuba's economic reforms.
For upper- and middle-class parents, the schools are filling gaps in subjects such as English, dance, painting, music and theater - invaluable in a country where artists and tourism industry workers can feed their families far more easily than the average state employee. English is also vital for Cubans migrating to the United States, their numbers nearly doubled since the two countries declared detente in late 2014.
The economic reforms of the last five years have created a large class of private entrepreneurs with lifestyles most Cubans can only dream of. That class has been flooded with cash from a 17 percent surge in the number of tourist visits and a wave of private investment from Cuban emigres launched after detente was announced.
The special schools mean the children of the privileged are increasingly getting a leg up, threatening to root inequality deeper and more broadly in a society where it isn't supposed to exist at all.
"It's just splintering the collective identity, stratifying society more and making the gap between the haves and have-nots great," said educational anthropologist Denise F. Blum, author of a 2011 study of Cuban education titled "Cuban Youth and Revolutionary Values: Educating the New Socialist Citizen."
"I think it's changing what socialism means for Cuba," Blum said.
President Barack Obama travels to Cuba this month to push for such changes - a loosening of state control that allows a middle class to develop independently from the single-party government and the centrally planned economy it controls.
"The diversification of the economy is ultimately a source of a change for the Cuban people because they have more control over their own lives," Deputy National Security Adviser Ben Rhodes, one of the architects of Obama's new policy, told The Associated Press.
Parents with the means are spending about 250 Cuban pesos ($10) a month, around half the average state worker's salary, to give their children early advantages in English and the arts. Math and science are also taught privately, in less formal settings that more closely resemble group private tutoring.
"It's a sacrifice for every Cuban but we try to do it for them, for their future, so that they can get ahead in life," said Doralkis Vinas, a homemaker whose husband works in a private automobile body shop.
Their son Julito takes English at the Cuban School of Foreign Languages, which opened five years ago and now has four branches in Havana and two opening in western Pinar del Rio province.
The network, known by its Spanish acronym ECLEX, has hired a staff of moonlighting or retired public school teachers like Lage, who retired from the University of Havana last year after 37 years teaching English.
The project has about 800 students across Cuba, said Yureibys Perez Blanco, the school's director-general, making it among the biggest of about 30 private English institutions in Havana. Besides elementary English, it is starting to offer specialized courses for law, accounting, management, medical English and tourism, she said.
She said there's a need for better English instruction for children in public schools, where there often aren't enough qualified teachers to give weekly English classes. To help, each of the ECLEX branches adopts a needy school nearby and sends a teacher there to teach the weekly English lesson to the class that needs it most.
"We don't have divisions in social classes here but we know that people have different purchasing power," she said. "We have students here whose parents have families overseas that help them financially a lot. We have students whose parents live off their government salaries and save 250 pesos for English school so their kids can be better prepared."
Private education has also transformed arts education. The country's elite government arts schools have three sets of competitive entrance exams: for elementary school, high-school and the prestigious Superior Institute of Arts university. Cuba prides itself on its achievements in the arts and its musicians, dancers, actors and fine artists have long been allowed to perform and sell their works outside the country. Many have become wealthy by Cuban standards, making an arts career a path to prestige and profit on the island.
"In our workshops, we realize that 95 percent of families come here with the idea that artists are famous, artists travel outside the country," said Angel Escobedo, head of a private Havana arts workshop called Entreartes. He said he has about 40 students aged 3 to 21 taking classes in dance, theater, music and fine arts like sculpture.
"They want to prepare themselves for the art schools with the objective of being famous, traveling," he said. "We're the specialists in preparing themselves for the entrance exams."
Relatively affluent Cubans say preparing their children for career success is just part of the reason they're sacrificing to pay for private education. Many say it's just as important to raise well-rounded children in a society that has long valued arts and language skills as the measures of an educated person.
"The singing teacher says she's the finest student he has," said Ireinaldo Hernandez, an airport catering services worker who sends his 9-year-old daughter Erika to Entreartes. "The dance professor says she's the one with the most flexibility. The sculpture teacher says she's coming along well. Until now we haven't been able to define the path for her to follow so she's in everything. Besides helping us decide, it's all preparation for her life, for her future."