The COVID-19 crisis has forced school closures in 188 countries, heavily disrupting the learning process of more than 1.7 billion children, youth, and their families. With the pandemic slowing down, governments are now developing the next steps of their strategy to cope with a crisis of an unprecedented scope. In many countries, it implies to plan the safe reopening of schools, and it has taken various forms. Some countries, such as France or Germany, have already welcomed back students, while others, such as Spain or Italy, will maintain the school gates closed until September. Despite these different reopening timelines that reflect national preferences and contexts, there is a broad consensus on the need to analyse and evaluate the consequences of school closures (Gouëdard, Pont and Viennet, 2020[1]).

Country representatives attending the yearly meeting of the OECD Implementing Education Policies project (June 2020) expressed their particular interest in measuring the potential learning loss associated to school closures. In the OECD-Harvard Graduate School of Education Survey, the impact of school closures on education continuity was estimated to be at least 2 months of instruction for half of the primary and secondary school students (Figure 1). During this time, distance-learning solutions such as online classrooms, TV and radio broadcasts, and computer-assisted learning were implemented to bridge the gap between schools and learners, but the overall impact on learning remains uncertain.

In labour economics, hysteresis usually refers to the long-term effect of unemployment on a worker’s ability to find a job. It could refer in education to the long-term impact of school closures on students’ outcomes. During the COVID-19 crisis, and in the absence of traditional schooling, we expected that levels of learning would not match what face-to-face teaching would have achieved. For instance because it takes time to adapt and switch to distance-learning, international reports already highlighted the difficulties schools face to integrate the technologies of information and communication into the classroom (OECD, 2018[3]; OECD, 2019[4]). This potential learning loss is determined by two concurring factors.

On the one hand, how much students have learnt during school closures — the “intensive margin” — refers to the efficiency of education continuity solutions. It is now the focus of analysis in many countries, as they aim to identify the most efficient distance-learning tools. This discussion is necessary to guide the research agenda, and capitalise on the crisis momentum to shape the future of education. According to Hattie (2020[5]), we should not, however, overly focus on the impact of school closures on students’ learning. He recalls that the literature has only shown “tiny” effects of the school year length on students’ outcomes, and that the Christchurch earthquakes in 2011, which led to prolonged school closures, did not undermine students’ performance in school examinations at the end of the year, mostly because teachers focused afterwards on "what has to be learnt".

The effects of 2 months of disrupted learning may fade out by the time students complete their school education.    

On the other hand, how many students who continued to learn during the school closures — the “extensive margin” — refers to the share of students engaged in the education continuity solutions. It reveals a different issue, as distance-learning solutions are often associated with attendance challenges and higher absenteeism. Between 5 and 8% of French students could not be reached by their teachers two weeks after school closures, according to the French Minister of Education (LesEchos, 2020[6]). In Los Angeles (United States), the nation’s second-largest school district, around 13% of high school students still had not had any contact with teaching staff three weeks following the lockdown (The New-York Times, 2020[7]). These attendance challenges, still largely undocumented, increase the risk of disengagement or dropout, especially among students in difficult socio-economic and family situations.

This risk, acknowledged worldwide (Saavedra, 2020[8]), prompts the existence of a potential hysteresis of the COVID-19 crisis in education as some students went off the grid during the school closures (Figure 2). It stems from the many elements, often linked to the socio-economic background, leading to a withdrawal from the school system that will induce a long term impact on students’ outcomes. Such elements encompasses for instance the struggle some students face to maintain their learning pace from home due to inadequate resources; the erosion of their basic academic skills due to lack of practice; the difficulty in re-engaging with education activities; their demotivation as they fall further behind; and the curbing of their educational aspirations due to the uncertainty of the learning environment. Given the critical role proper IT resources and parental involvement have played in ensuring education continuity during the crisis (Gouëdard, Pont and Viennet, 2020[1]), the hysteresis induced by school closures may be more prevalent among students from less privileged backgrounds.

The hysteresis induced by school closures may be more prevalent among students from less privileged backgrounds.   

Against this backdrop, governments should not solely focus on the short-term effects of the 2 months of disrupted learning, which may fade out by the time students complete their school education. The policy focus should be set on keeping students engaged in learning to limit hysteresis, the long term impact on students’ outcomes, which also potentially aggravates inequalities in education. This requires to pay careful attention to the indicators that will determine how the COVID-19 crisis will influence students’ outcomes in the long term, such as the curbing of their educational aspirations and in extreme cases, their dropping-out rate.

Some countries have developed initiatives to limit dropout during school closures. In Spain, students from the “Second Chance Schools” (Escuelas de Segunda Oportunidad, E2O), a network of schools providing 15-29 year old not in education, employment, or training (NEET), an original pedagogical model, benefitted from individualised follow-ups carried out by telephone, in which academic, health and personal doubts were discussed (CEDEFOP, 2020[9]). In England and Wales (United Kingdom), schools remained open to vulnerable children and young people, those either supported by the social care system or identified as vulnerable by educational providers and local authorities (Department for Education, UK, 2020[10]). In Germany, social pedagogues called “transition coaches” support students at school to limit dropouts and ensure they complete general or vocational education. During the pandemic, transition coaches have adjusted their services to ensure the continuity of tailored support, providing advice to young people as much as possible by phone (CEDEFOP, 2020[11]).

For countries now defining their mid-term strategies, the potential long-term educational impact of the crisis requires these countries to pursue a double objective. First, there is an urgency to collect comprehensive data to gain an accurate picture of dropouts or disengaged students during school closures, develop specific support to bring those students back to school, and engage in diagnostic assessment to identify their learning needs. The OECD Project for International Student Assessment (PISA) is currently developing a specific questionnaire module to build a comparative dataset and document the educational impact of the crisis across countries (OECD, 2020[12]). In the meantime, governments can establish different forms of targeted communication to reinitiate contact with disengaged students, and adopt a flexible curriculum centred on key competences to restore students’ confidence. Second, countries need to prepare strategies to mitigate effectively this risk in case of future lockdowns. This can include among others:

  • To monitor closely student engagement by following up on their attendance, behaviour, and learning progress.

  • To address the potential barriers to student engagement by offering adequate resources (such as laptops or tablets, and safe places to learn).

  • To provide individualised support to students so they can get the best out of the new modes of education delivery (Gouëdard, Pont and Viennet, 2020[1]).


[9] CEDEFOP (2020), Digital gap during COVID-19 for VET learners at risk in Europe, (accessed on 18 June 2020).

[11] CEDEFOP (2020), Note on lifelong guidance and the COVID-19 pandemic:, (accessed on 18 June 2020).

[10] Department for Education, UK (2020), Guidance: Supporting vulnerable children and young people during the coronavirus (COVID-19) outbreak - actions for educational providers and other partners, (accessed on 18 June 2020).

[1] Gouëdard, P., B. Pont and R. Viennet (2020), “Education responses to COVID-19: shaping an implementation strategy”, OECD Education Working Papers, No. 224,

[5] Hattie, J. (2020), Visible Learning Effect Sizes When Schools Are Closed: What Matters and What Does Not, (accessed on 18 June 2020).

[6] LesEchos (2020), Coronavirus : « Entre 5 et 8 % des élèves » sans continuité pédagogique depuis la fermeture des écoles, (accessed on 18 June 2020).

[12] OECD (2020), PISA 2021 Adjusted Design, (accessed on 18 June 2020).

[4] OECD (2019), PISA 2018 Results (Volume II): Where All Students Can Succeed, PISA, OECD Publishing, Paris,

[3] OECD (2018), The Future of Education and Skills: Education 2030, OECD Publishing, Paris,

[2] Reimers, F. and A. Schleicher (2020), Educational Opportunity during the COVID-19 Pandemic.

[8] Saavedra, J. (2020), “Educational challenges and opportunities of the Coronavirus (COVID-19) pandemic”, Worldbank Blogs, (accessed on 18 June 2020).

[7] The New-York Times (2020), As School Moves Online, Many Students Stay Logged Out, (accessed on 18 June 2020).

For further information

Gouëdard, P., B. Pont and R. Viennet (2020), “Education responses to COVID-19: shaping an implementation strategy”, OECD Education Working Papers, No. 224,

OECD (2020), “Education responses to COVID-19: an implementation strategy toolkit”, OECD Publishing, Paris,


Pierre Gouëdard (✉ )

Beatriz Pont; (✉


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