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From VOA Learning English, this is the Health Report. Green spaces are ones filled with plants, trees, and flowers. But these days, outdoor time competes for a child’s attention with indoor activities like computers, television and electronic games. Spanish and U.S. researchers studied whether a lack of outside activity in green spaces affects school work. Doctor Payam Dadvand works at the Centre for Research and Environmental Epidemiology in Barcelona, Spain. He and his team studied more than 2,600 children from 36 schools in the city. The kids were seven to 10 years old. The researchers used information from satellites to learn how much green space surrounded each school. Over one year, the children took computerized tests four times to measure memory and attention span. The researchers then compared the amount of green space near each school with the test scores. They found that the children who were close to more green space had a better ability to memorize and were more attentive. The team says air quality is the main reason for the results. Trees help reduce air pollution. However, some experts question using satellite images to determine the amount of green space. Others say this study does not consider other factors in the schools. But the findings of that study seem to support a six-year study on elementary schools in the U.S. state of Massachusetts. Researchers there studied students at 905 schools from 2006 to 2012. They found that children in schools with more green spaces scored higher on standardized tests.