Schools possess a lot of data that teachers can use to improve their teaching and schools. However, data use studies in schools is concentrated in a few developed nations. This study explored data available, its use, and promoting or hindering factors in three Kenyan schools and was based on factors hypothesized to influence data use in organizations. To answer the research questions, qualitative data was collected using interviews and document analysis and was analyzed using NVIVO program that allows for coding of themes in line with research questions and conceptual framework. Results show that schools have similar data types available, and similar factors promoting or hindering the use of data. The study further shows that school leaders mainly use school level data to monitor, plan and develop policies for school, curriculum and teacher improvement respectively, while teachers use classroom level data to plan their lessons and monitor students’ progress. Furthermore, professional development in the use of data is needed, as well as investing in data systems and technology. The study recommends ‘parents and students’ as a new factor that promote or hinder data use in schools.