were national in scope, with the exception of Nigeria, where surveys representative at the state level were implemented in four states (Anambra, Bauchi, Ekiti, and Niger).

Representative surveys of between 150 and 760 schools were implemented in each country or Nigerian state using a multistage, cluster-sampling design. Primary schools with at least one fourth-grade class formed the sampling frame. The samples were designed to provide representative estimates for teacher effort, knowledge, and skills in public primary schools, broken down by urban and rural location. For five of the six non-pilot surveys, representative data were also collected for private primary schools. Across the eight surveys, the SDI collected data on 2,600 schools, over 21,000 teachers and 24,000 students in Sub-Saharan Africa.<sup>2</sup> The surveys collected a broad set of school, teacher, and student specific information, with an approach that relies as much as possible on direct observation rather than on respondent reports. Data were collected through visual inspections of fourth-grade classrooms and the school premises, direct physical verification of teacher presence by unannounced visits, and teacher and student tests. We focus here on the data on teacher behavior and knowledge.<sup>3</sup>

# **3. The starting point: Learning outcomes in primary schools in Africa**

In the last decade, the major International Association for the Evaluation of Education Achievement (IEA) and OECD testing programs have expanded dramatically, with more than 100 participating countries in at least one of these assessments in 2012 (Hanushek and Woessmann 2015). However, only one Sub-Saharan African country (Botswana) participated in the last IEA mathematics tests at the primary level, and only three countries participated at the secondary level (Botswana, Ghana, and South Africa).<sup>4</sup> Average test results at the secondary level for these three countries suggest _average_ test scores below the lowest _5th percentile_ score in the US. A significant share of students, however, performed worse than chance (based on multiple choice items), suggesting that the tests are potentially unreliable at pinpointing performance at such low levels (TIMSS 2011).

As part of the SDI assessment of teacher behavior and knowledge, fourth-grade students in sampled schools were assessed in basic reading, writing, and arithmetic skills. While other

> 2 More details on the sample are available in an Appendix available from the authors upon request.

> 3 More information on SDI can be obtained at www.worldbank.org/sdi.

> 4 The Trends in International Mathematics and Science Study (TIMMS) by the International Association for the Evaluation of Education Achievement (IEA) test Grade 4 (primary) and Grade 8 (secondary) students on common elements of primary and secondary school curricula. In Botswana, Grade 6 students were assessed, as it was deemed too difficult for fourth-grade students to take the TIMSS fourth-grade assessment. Similarly, in Botswana and South Africa, ninth-grade students were assessed with the TIMSS eighth-grade assessment. No Sub-Saharan African country participated in the testing program run by OECD (Programme for International Student Assessment, PISA).

6