The Australian Council for Educational Research (ACER) has created an open-access classroom observation tool based on research conducted for the Australian Department of Foreign Affairs and Trade's (DFAT) Teacher Development Multi-Year Study Series, which studied teaching practices in Timor-Leste, Vanuatu and Lao PDR (see https://research.acer.edu.au/eas/). This comprehensive tool is designed to capture various aspects of teaching and learning in the classroom. It aims to help education researchers and practitioners gather evidence of teaching practices, particularly in the early grades of primary education in low- and middle-income countries. The tool is also intended for use by local observers, regardless of their teaching or observation experience, to consistently and reliably make observations.