Around half of Scottish 15-year-olds were attending schools where the headteachers reported that instruction was hindered by both a shortage of teachers and other school staff, according to new figures.

Teacher recruitment levels are identified as crucial in a report from the Organisation for Economic Cooperation and Development (OECD), released today.

The report, Pisa 2018 Results: effective policies, successful schools, states: “Out of all the school resources that are needed to boost students’ learning and wellbeing, teachers are perhaps the most important. If schools do not have a sufficient number of teachers, or if teachers are not adequately qualified and able to support their students’ needs, improving the quality and equity of education is unlikely.”

Background: Pisa results 2018 - what happened in Scotland?

Opinion: What does Pisa tell us about Scottish education?

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In England, only 26.5 per cent of 15-year-olds were attending schools where a lack of teaching staff was highlighted as an issue; the OECD average was 27.1 per cent.

Many teachers in disadvantaged schools ‘not fully certified’

The figures also show that whilst Scotland prides itself on having a highly qualified teaching workforce, headteachers in “socioeconomically disadvantaged schools” reported that only 77.1 per cent of teachers were “fully certified by the appropriate authority”. In “socioeconomically advantaged schools” that figure was 98.7 per cent.

The report also looks at other important characteristics that the OECD says make for successful education systems. Children attending preschool for three years or more; smaller class sizes; more extracurricular activities; an adequate number of teachers; more fully certified teachers; more extracurricular activities.

Key statistics include:

94% The proportion of teachers fully certified by the appropriate authority, although this figure fell to 77.1 per cent for disadvantaged schools (as reported by Scottish secondary headteachers)

48.6% The proportion of 15-year-olds in schools where the headteacher reported that the school’s capacity to provide instruction was hindered by a lack of teaching staff (the OECD average was 27.1 per cent)

46.3% The proportion of 15-year-olds in schools where the headteacher reported that the school’s capacity to provide instruction was hindered by a lack of “assisting staff” (the OECD average was 32.8 per cent)

19.4% The proportion of15-year-olds in schools where the headteacher reported that the school’s capacity to provide instruction was hindered by a lack of educational material like textbooks or ICT equipment (the OECD average was 28.4 per cent)

25.4% The proportion of 15-year-olds who reported having attended preschool for three or more years. The majority, 47.2 per cent, reported attending preschool for at least two years but less than three.

98% The proportion of 15-year-olds who reported that they had never been asked to repeat a year in primary, rising to 99.2 per cent in upper secondary.

96.3% The proportion of headteachers who reported grouping by ability into different classes in some subjects (the OECD average was 34.5 per cent).

78.8% The proportion of headteachers who reported grouping by ability within classes in some subjects (the OECD average was 48.7 per cent)

25.5 Average class size (the OECD average was 26.1).

99% The proportion of 15-year-olds in schools where the headteacher reported that the school offered extracurricular activities such as band, orchestra or choir, and sporting activities (This proportion fell to 84.2 per cent when it came to offering these students the chance to take part in a school play or musical, and to 51.9 per cent when it came to a school yearbook, newspaper or magazine).