The Ultra-Low Emission Zone (ULEZ) was launched in central London in 2019. Cars that don’t meet strict emission standards must pay to drive into the zone. Today, it’s reportedly the largest clean air zone in the world. Researchers from Cambridge University set out to find whether ULEZ had changed how kids get to school. They found that 4 in 10 kids who were driven to school now walk, cycle or use public transport compared with 2 in 10 kids from Luton, a nearby town outside the ULEZ.