In the rapidly developing digital world, technology is and will be a force in workplaces, communities, and everyday lives in the 21st century. Information and Communication Technology (ICT) including computer hardware/software, networking and other technologies such as audio, video, and other multimedia tools became learning tools for students in the 21st century. ICT also changed the nature of the teachers' work and the way they relate to other teachers in their professional lives. The researcher designed and implemented a course to enhance 18 pre-service science teachers' professional knowledge, which knowledge of instructional media and technology is one of the important domains. Technology was used as a tool for enhancing the development of professional knowledge in a seminar organizing activity in which students designed instructional movies and participated in online discussion activities. Data from questionnaires, classroom observation, journals, online discussion boards, and pre-service science teachers' artifacts were analyzed by the constant comparative method. The results revealed that most of the pre-service science teachers felt more comfortable using software and hardware, were willing to learn, improve their creativity, participate in group collaboration, and felt free asking questions and reflecting on their ideas on discussion boards. The results show that pre-service science teachers develop their professional knowledge when they are engaged in embedding ICT in subject teaching activities. (Contains 4 tables and 1 figure.)