During the past year, teachers have expended much time and effort moving their mathematics instruction online. To do this, teachers had to build their content, pedagogical, and technological knowledge, or technological pedagogical content knowledge (TPACK). As teacher educators facilitating a professional learning sequence during the shift to remote instruction, the authors were privileged to work with a group of K-2 teachers who drew on their mathematical pedagogical content knowledge to build their technological knowledge. In this article, the authors provide a window into the complexity of this work by detailing how they collaborated with the teachers to (re)design three-act tasks for the synchronous and asynchronous online learning environment. They then connect these examples to the TPACK framework to discuss considerations for teaching primary mathematics online.