The relationship between teacher support and disciplinary climate is explored further in the following section of this paper on the school learning environment, which examines the key factors within schools that facilitate teacher support.
Teacher support is also influenced by staffing levels at schools. System-level analyses reveal that, across OECD countries, changes between 2018 and 2022 in the proportion of students enrolled in schools where the school principal reported that the lack of teaching staff hinders student learning (i.e. teacher shortage as perceived by school principals) are negatively related to changes over the same period in the proportion of students who reported that their teachers give them extra help when they need it (Table B.31). In other words, teacher support tended to decline in OECD countries where perceived teacher shortages increased, and vice versa. When all countries and economies with comparable data are considered, this correlation is not found. Within countries, findings reveal that students in schools where principals reported teaching staff shortages hindering student learning received less support from their teachers, on average, across OECD countries. However, this pattern is only observed in a minority of countries participating in PISA 2022, suggesting that teaching staff shortages are not universally linked to reduced teacher support (Table B.20). At the country level, the relationship between teacher support and teaching staff shortages is characterised by a weak negative correlation; countries with a higher average level of teacher support tend to have a lower proportion of students in schools facing teacher shortages (Table B.31). These results highlight the potential impact of resource constraints on teacher-student interactions, while also underscoring the complexity of this relationship across different national contexts.
Interestingly, changes in perceived teacher shortages between 2018 and 2022 do not appear to correlate with actual changes in the student-teacher ratio over the same period (Table B.31). Although school principals in 2022 reported more teacher shortages than in 2018 in many education systems, the student-teacher ratio was stable or even declined in most countries/economies over this period.2 This suggests that principals’ heightened concerns about teacher shortages may not be solely linked to the number of teachers. Other potential contributing factors could include teacher absenteeism, variations in teacher quality, an increasing number of students who need help, emerging issues such as digital distractions, shifts in the role of teachers, or evolving expectations towards teachers. Further research and analysis are needed to fully understand what is driving principals’ increasing concerns about teacher shortages.
Another potential explanation for the drop in reported levels of teacher support is the impact of the COVID-19 pandemic, which peaked in 2020 and 2021. As shown in Figure 10 below, the four teaching support practices measured in PISA increased slightly or remained stable on average across OECD countries prior to 2018. However, these results should be interpreted cautiously, as the question on teacher support referred to science in PISA 2015, reading in PISA 2018, and mathematics in PISA 2012 and 2022. It is therefore unclear whether observed differences are due to changes over time or variations in support practices among teachers of mathematics versus science or reading. Based on an untested assumption that teacher support does not vary significantly across different subject domains, the impact of the pandemic on the decline in teacher support cannot be denied, as the decline seems to occur only after 2018. PISA 2025 will provide an opportunity to assess whether the decline in teacher support is a temporary phenomenon linked to the pandemic or part of a more persistent trend.
Trends in class size might have mitigated other factors contributing to a decline in teacher support. According to PISA data, the average class size of classes attended by 15-year-olds across OECD countries decreased by approximately one student between 2012 and 20223 (Table B.30). Moreover, students in smaller classes reported higher levels of teacher support, on average across OECD countries (Table B.29). However, data also reveal that countries and economies with higher average class sizes in mathematics tend to have higher levels of teacher support in mathematics lessons (Table B.31).
Other contextual aspects not analysed in this paper could also have an influence on changes in teacher support over time. Examples of such aspects include the increasing use of smartphones in schools (OECD, 2023[2]) and, in certain countries, greater classroom diversity due to immigration and demographic trends (OECD, 2025[13]; Forghani-Arani, Cerna and Bannon, 2019[14]).
