An increase in science and maths requirements in U.S. high schools has lead to higher dropout rates, recent research has found.
Researchers analysed census data for educational attainment from 1990 onwards.
Drop out rates rose to 11.4% when students were required to take six maths and science courses to graduate, compared to 8.4% when requirements were lower.
African-American males at schools with the toughest graduation requirements had a dropout rate of 23%.
High school dropout has been linked to health problems and lower quality of life.Read more at Washington University in St Louis