Education Minister Heng Swee Keat congratulated local teenagers for doing well in the Programme for International Student Assessment (Pisa) in a Facebook posting on Wednesday.

Singapore came in second in mathematics and third in science and reading in the most recent Pisa test carried out last year. The test measures how well students use mathematics, science and reading to solve real-world problems.

"Regardless of how they rank relative to students from elsewhere, our students' own scores are better this time than when we first took part in Pisa in 2009," said Mr Heng, adding that this means the education system is moving in the right direction.

"Even more important - and this is a point of pride for me - our weaker students did better this year, so we know improvement is across the board," he said.

Mr Heng said that Pisa tests critical thinking, and in order to do well, students "can't get by with just memorisation; he must have real knowledge and the wits to apply that knowledge to unpredictable real-life problems".

"This is exactly what we want our students to learn in school - the real skills to think critically and creatively so they can succeed in the 21st century," he said. He added that the improvement shows that Singapore's teaching strategies to expose students to real-life issues are working.