Recently, people in the US education have got extremely worried because a new report has shown that American students have a maths problem.

    The 2015 Programme for International Student Assessment(评估)(PISA) shows maths scores in the US getting lower and no improvement in science or reading. PISA tests 15-year-olds from different countries and regions in their maths, science and reading skills. About 540,000 students from 72 countries and regions took part in the assessment in 2015.

    US scores in reading and science were about the same as three years ago, leaving Americans near the middle of the bigger group. But the situation in maths is much more worrying. The US average score was 470,below the OECD(经合组织) test average of 490,meaning the US was No.40 among the 72 countries and areas. It was 12 points lower than in 2012 and 18 points lower than in 2009. So, what is going on with American students' maths skills?

    One reason may be that the US does not teach maths in enough depth." Students are often good at answering the first part of a problem in the United States," said Andreas Schleicher, director of education and skills at OECD." But as soon as students have to go deeper and answer the more complicated part of a problem, they have difficulties." In comparison, many high-performing countries and regions in maths teach a lot less but focus in much greater depth, especially when you look at East Asia, Japan and Singapore, according to Schleicher.

    Another reason may be the fact that many people in the US are unwilling to travel to foreign countries to learn better teaching practices." One of our biggest challenges in the US is that the teachers are not going out and seeing what high-performing countries do differently," said Wendy Kopp, who started Teach for America ,in a news programme.