2021. Summer: We sent invitation e-mails to 2,743 primary schools, out of which 212 had the wrong e-mail address. We reached 2,531 primary schools out of 3,834 primary schools. We invited all 5th-8th grade teachers teaching grammar and literature or mathematics to respond to our online survey. The fieldwork lasted between 18 June and 6 September 2021. There were 413 teachers who participated in the survey. Respondent teachers were, on average, 49.9 years old (SD = 8.9) and had an average teaching experience of 21.9 years (SD = 10.5).
2022. February: We sent invitation e-mails to 1,892 primary schools out of 3,834 primary schools. We have not sent e-mails to those schools that provided wrong e-mails or informed us in prior waves that they do not want to receive e-mails from us. We invited all teachers to respond to our online survey. N=656 teachers from 288 schools participated in our survey.