organizational psychology (e.g. Heslin, Latham and VandeWalle 2005) have revealed how fixed mindsets can be shifted and how this can help improve motivation and performance. This paper also highlights the importance of further exploring this line of work.

Our paper is organized as follows. Section 2 provides information on data, estimation strategy (including a conceptual introduction to the CIF and LASSO algorithms), and limitations; Section 3 provides a descriptive analysis of teacher-level and other covariates, Section 4 presents the main results, and Section 5 concludes.

# **2. Data, Methodology, and Limitations**

## **2.1 Data**

This study is a part of the Research on Improving Systems of Education (RISE) program for Tanzania, wherein several researchers are using the same data for different studies looking at various aspects of the Tanzanian education system and reform.<sup>5</sup> The data for this paper comes from 392 schools randomly sampled from 392 wards across 22 districts in 6 representative regions across Tanzania. Our final sample includes 436 teachers and 3,019 students. The baseline survey was conducted between February-May 2019 and the follow-up survey between January-April 2020, targeting 748 teachers and 6,586 students from Grades 2 and 3.

Three instruments were used to collect data on teacher covariates. These include a detailed teacher survey which also has a dedicated module on teacher mindsets; a teacher subject content knowledge assessment; and classroom observation of teachers using the _Teach Classroom Observation_ tool.<sup>6</sup> For the detailed teacher survey, 10 teachers were randomly selected from the complete teacher roster for the school provided by the head-teacher. To the extent possible, the survey was targeted at teachers teaching Math and Kiswahili in Grades 2 and 3. After the survey, only the Grade 2 and 3 teachers were invited to take the teacher assessment. Teacher assessments were subject-based and linked to the curriculum. For Kiswahili, teachers were expected to read a short text and answer 8 comprehension questions, while for Math they answered 10 questions about basic algebra operations and geometry.

Finally, in each school, one Grade 2 and one Grade 3 teacher were randomly selected for classroom observation using the _Teach_ Classroom Observation tool (Molina et. al. 2018). _Teach_ allows enumerators to rate teaching practices through two 15-minute observations during a lesson. The practices are organized into nine dimensions: Supportive Learning Environment, Positive Behavioral Expectations, Lesson Facilitation, Checks for Understanding, Feedback, Critical Thinking, Autonomy, Perseverance and SocioEmotional Skills. These dimensions are measured on a five-point scale and then averaged across the two 15-minute observations.

The study also included a student survey and student assessment. For each school, around 20 students (10 each from Grades 2 and Grade 3) were randomly selected from a list of all Grade 2 and 3 students (provided by the head-teacher). Students were tested on foundational concepts in Math and Kiswahili. These tests

> 5 For more details see: https://riseprogramme.org/countries/tanzania

> 6 <u>https://www.worldbank.org/en/topic/education/brief/teach-related-blogs</u>

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