A teacher teaches a class to students of the Felix Rodriguez de la Fuente school, as part of a project known as 'Aire Limpio' (Fresh Air) at the Playa de los Nietos (The Grandchildren's Beach), which aims to use better air quality for children during the coronavirus disease (COVID-19) pandemic, near Cartagena, southern Spain April 8, 2021. Picture taken with a drone. Picture taken April 8, 2021. REUTERS/Nacho Doce