# **Introduction**

There is a learning crisis (World Bank 2017). It existed before COVID-19 (Angrist et al. 2021, 2022) and it is global. It has been exacerbated since the school closures began in March 2020 (McKinsey 2022).

COVID-19 caused significant disruption to the global education system. Early in the pandemic, the World Bank (Azevedo et al. 2021) presented simulations of the potential effect of school closures on learning outcomes. It forecast significant declines in the global level of schooling and learning outcomes. School closures could result in a loss of 0.3-1.1 years of schooling and students from the current cohort could, on average, face a reduction of $366 to $1,776 in yearly earnings. Globally, a school shutdown of 5 months could generate learning losses that have a present value of $10 trillion.

Early reviews of the first wave of lockdowns and school closures suggested significant learning loss in a few countries (see, for example, Engzell et al 2021; Haelermans et al. 2022; Jack et al. 2022; Maldonado and De Witte 2022). More recent and thorough analyses of recorded learning losses documented since the beginning of the school closures in March 2020 find even more evidence of learning loss (Donnelly and Patrinos 2021). Robust studies suggest learning losses on average amounting to 0.17 of a standard deviation, or at least one-third of a year's worth of learning (Betthäuser et al. 2023; Hammerstein et al. 2021; Patrinos et al. 2023; Zierer 2021). Most studies observe increases in inequality where certain demographics of students experienced learning losses that were more significant than others. But there are also outliers, countries that managed to limit the amount of loss.

The Progress in International Reading Literacy Study (PIRLS) is the largest international test of 4<sup>th</sup> -grade students’ reading achievement. It is the largest international assessment of reading skills at the primary school level. The 2021 edition was implemented when most countries reopened schools after closures related to the COVID-19 pandemic. Comparing the results from the previous editions conducted in 2001, 2006, 2011, and 2016, one can estimate the impact of the school closures and online teaching in the pandemic on student reading skills. Evidence from individual countries suggests that in many cases students in primary schools suffered larger education losses due to distant teaching in the pandemic. Moreover, the results suggest that the decline is larger among the low-achieving students. Finally, some research shows that the pandemic affected student attitudes, motivation, and well-being.

Negative consequences of the pandemic for students should be addressed through targeted policies aiming at groups of students with the larger losses and addressing their varying needs regarding attitudes and well-being. Changes in student performance might be driven by other factors than the pandemic and school closures. However, the COVID-19-related school closures are the only factor that is common to most countries.

Due to the emergency nature of the COVID-19 pandemic, education systems around the world are facing extreme disruption. At its peak, UNESCO (2020) reported that nearly 1.6 billion learners in more than 190 countries, or 94 percent of the world’s student population, were impacted by educational institution closures. Given the abruptness of the situation, teachers and administrations were unprepared for this transition and were forced to build emergency 2