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 simulation-based active learning 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 two assignments with Peer Review: 1) Select and evaluate an Activity Sheet and 2) Create your own Activity Sheet for science or math that integrate PhET simulations. This course is the third of four courses that make up the specialization 鈥淎ctive Learning in STEM with PhET Interactive Simulations鈥. This course is also available in Spanish as 鈥淒ise帽o de Actividades con Simulaciones PhET para la Educaci贸n STEM鈥 and in Portuguese as "Desenho de Atividades com PhET para Educa莽茫o STEM".