PhET Interactive Simulations ( https://phet.colorado.edu/ ), a project of the University of Colorado Boulder, provides fun, free, interactive, research-based science and mathematics simulations for use across, primary, secondary, and higher education levels. We extensively test and evaluate each simulation to ensure educational effectiveness. All simulations are open source and free to all students and teachers. In this course, we will review strategies for how to use PhET to create sim-based inquiry activities for math or science classes, including activity sheets that students can use as they work independently or in small groups while they have direct access to simulations on their own devices. To finish this course, you need to complete one assignment with Peer Review: Create an inquiry based activity worksheet for science or math that integrate PhET simulations. This course is the second of three courses that integrate the specialization “Active Learning in STEM with PhET Interactive Simulations”. This course is also available in Spanish as “Diseño de Actividades con Simulaciones PhET para la Educación STEM”