Politicians react to Wales' Pisa performance
3 December 2013 Last updated at 19:21 GMT
Wales has fallen behind the rest of the UK significantly in reading, maths and science for the third time, an international study has shown.
The tests in science, maths, and reading were taken by 500,000 15-year-olds in 68 countries.
In Wales, there were lower results on average in the three subjects than in England, Northern Ireland and Scotland.
Scotland leads the way in the UK in maths and reading, while England is ahead in science.
BBC Wales political editor Nick Servini looks at political reaction to the results.