Mexico City: Nearly two years after the pandemic first shut her classroom, Mexican schoolgirl Elena Delgado is struggling to avoid falling far behind in her studies — like millions of other children around the world. Another wave of coronavirus infections gripping Mexico following the emergence of the highly contagious Omicron variant have forced the nine-year-old to return to remote learning. “I really miss spending time with my friends. I also miss the teacher a lot,” she said. Elena is striving to catch up with what non-governmental organization the Espinosa Yglesias Study Center says could be between one and three years of lost learning for Mexican students. It is a global problem — in Brazil, the learning loss for high school students is estimated to be one year, compared with half a school year in Belgium, according to a study published by the center in September. “When I study online, I fall further behind,” Elena said, surrounded by dolls and toys in her bedroom. “When I’m in the classroom I can stop and ask the teacher to rewrite what was on the blackboard,” she added. The schoolgirl has taken private remedial classes in subjects including math and English, said her mother Elena Cabanas, a 41-year-old lawyer. Worries about the economic fallout of the pandemic led her parents to remove their daughter from a private school early in the crisis. She joined the 90 percent of Mexican students between the ages of three and 18 who attend free public schools. “During the whole of the second year at the public school she only had about five virtual classes and didn’t learn anything,” said Cabanas. Disappointed, the mother decided to put Elena back in private education, but she had her repeat the second grade. Elena’s mother worries that her daughter struggles with mathematical calculations. “When I was nine years old I already knew the multiplication tables from top to bottom,” she said. Some children have been even less fortunate. In the 2020-2021 academic year, 5.2 million students between three and 29 years old dropped out of basic and higher education in Mexico due to Covid-19 or for economic reasons, according to official data. In response to the pandemic, President Andres Manuel Lopez Obrador’s government introduced a home learning program via television, but with little or no interaction with students. After 17 months of remote learning, public schools resumed face-to-face classes in August 2021 on a voluntary basis. But last week, 12 of the 32 Mexican states chose to resume distance teaching due to the spike in coronavirus infections. The authorities have not executed any plan to reverse the lag caused by the disruption, said Luis Monroy-Gomez-Franco, a researcher at the Espinosa Yglesias Study Center and one of the authors of the study. “The impression is that there isn’t even an acknowledgment that there’s been a problem and that’s what’s worrying,” he said. Whether children can catch up depends on the financial and educational resources of each family, said Monroy-Gomez-Franco. Parents like Elena’s who went to university can help their children close the gap, while others in poor households will struggle to do so, he said. Elena has learned to deal with disappointment during two years of a pandemic that has left more than 300,000 people dead in Mexico — one of the world’s highest tolls. As well as the impact on her education, she also struggles with social isolation. “I make more friends when I go to school in person. That’s another effect of the pandemic,” she said.