The OECD launched the PISA survey nearly 20 years ago. What changes occurred during this period? What are the countries that have shown most progress and those in which the situation has worsened ?

The PISA survey is now recognized in countries across the globe, which was not the case when it was launched 20 years ago. The OECD had to fight to have the survey’s methodologies approved by all, and to demonstrate its relevance to the various countries involved. This is a key achievement for PISA: boundaries have been overcome! Debates on education, which used to be restricted to the national level, have grown in number and have now reached an international level. Comparing ourselves to others enables us to constructively question ourselves.
Improving an education system is not only about enhancing academic performance, it is also about social equity. Indeed, for a system to be effective, it needs to be fair. The results of the 2015 PISA survey show that a growing number of countries succeed in combining quality and social equity. Generally speaking, there is positive progress and the survey attests of an increasing geographical diversity. Overall, countries in Asia are doing well, although success is not limited to this continent. Various Western countries, like the United Kingdom, Portugal, Canada or Australia, have also managed to improve the fairness of their systems.
In Europe, the OECD has been quite critical with regard to Sweden, despite its initial good ranking. In the first PISA survey in 2000, the country scored well on both academic performance and social equity. The situation has since then deteriorated. We think this can be partly explained by the implementation of a flexible school mapping policy, which allows parents to freely choose in which schools to enroll their children. As a result, children from privileged backgrounds have increasingly been attending the same schools. Sweden is backtracking, and its entire system is becoming more unequal. Moreover, other countries, like the United Kingdom or New Zealand, have also tried to give school mapping more flexibility, which led to increasing social inequalities. In light of these observations, it seems important that France does not to follow such a path.
France faces a challenging situation: its scores are average, its education system remains unequal, both its students and teachers have lost faith… What can be done to change this? Did the former majority (2012-2017) do well according to you? Are the first measures decided by the new majority encouraging ?
I share your view and it is important to note that this diagnosis is widely consensual, which is, to me, a form of progress. The first reactions to the PISA surveys were very critical, as French public opinion refused to recognize the diagnosis it revealed. Acceptance is the first step, and I am glad we are now aware of our weaknesses, as it increases the chances to later correct them.
We need to stop being so fatalistic. Too often it is said in France that inequalities cannot be fought: this is absolutely wrong! This widespread pessimism is all the  more regrettable as recent international studies show that countries such as the United Kingdom, whose population is heterogeneous and sometimes socially divided, were able to become more equal in only 10 years, thanks to selective reforms.
For a number of countries, several key levers, such as teacher training, proved successful. The quality of a given education system can never transcend that of its teachers. Many education systems suffer from inadequately trained teachers. The initial training is thus crucial; however, of all the OECD countries concerned, French teachers are the least well prepared. Indeed, according to the TALIS survey on secondary schools, 4 teachers out of 10 in France are ill-trained on pedagogy. The same investigation highlights the teachers’ insufficient access to a targeted professional training, depending on their specific requirements (the use of digital technology and personalized support for pupils being first on the list). It therefore seems essential to invest so as to allow the best-trained teachers to work with the students struggling the most. This proposal is motivated by an international observation: the least unequal countries are those which have massively invested in disadvantaged schools.
Since 2012, at first sight, reforms carried out in France to improve students performances seem to be moving in the right direction: investments in primary schools, in disadvantaged schools or even attempts to review teachers training. The OECD remains nonetheless critical on the implementation of such reforms. We tend to think that, once a law is passed, the difficult part is over. On the contrary, this is where it all begins! In our point of view, both the implementation and assessment of reforms are deficient in France. France should foster experimentation supported by research, and generalize successful practices.
The new majority first measures are going in the right direction, in particular in their will to make educational institutions more independent, to invest in primary schools or even in the bonus payments provided for teachers working in priority education zones. There is an entire set of encouraging reforms that have been announced by the government. However, I deeply regret that we are once again confronted with a debate on school timetables. What matters most are issues regarding the quality of education, and the connection between good practices and relevant school timetables. What allows teachers to be most efficient ? How can they develop one-on-one support ? When do we use digital tools ?
Similarly, if we let municipalities decide of their own school timetable (4 or 5 days), it would be appropriate to draw some boundaries to their decision-making, in order to avoid that the main criteria be budgetary rather than related to the students’ well-being. Generally, the OECD is quite critical on French reforms, too often focused on quantity – the means – rather than on the very quality of its system.
What are the main challenges European countries could face by working together in order to improve their education systems ? We have made a habit of talking about South Korea or Finland as role models. Are there any other models public authorities should pay attention to ?
Europeans face two main challenges in terms of educational systems.

First, they need to invest more in the first levels of elementary education: pre-primary education and primary school. This is where inequalities are formed, and later crystallize.
Second, some European countries struggle to offer good quality education. This is often because the teaching job is too unattractive. On the contrary, in Finland, being a teacher is particularly valued. Same thing Germany and Switzerland, where teachers are well-paid. In Southern European countries, where wages are low, these jobs remain unattractive.
Since 2000, the debate focused on both South Korea and Finland, but many other countries’ models are also worthy of interest. Australia, Quebec, Portugal, the United Kingdom or Estonia all have very different education systems, but all of them are successful and fair. One of the main lessons learned from PISA surveys is that there is more than one road to success. What all these countries have in common is their ability to invest in the teachers’ initial and continuous training, and their attractive pay for those who teach in disadvantages schools. We have a salary indicator which reveals that a teacher in South Korea or Germany earns almost twice as much as a teacher in France, both at the beginning or in the middle of their career. Furthermore, the best trained students are also the most motivated to become teachers in these two countries. Over the past surveys, French students’ level in maths has been declining, as graduating scientists are rather attracted by more lucrative sectors within the labor market.
TIMS studies (Trends in International Mathematics and Science Study, which are not studies carried out by the OECD) indeed show that France cruelly lacks well-trained maths teachers: it was ranked last on the list in 2015. Finally, it appears that French teachers are the least well-prepared to teach maths to students with difficulties, which isn’t surprising as most of them have a literary background and their own set of complexes.