As the success of distance learning (DL) has driven universities to increase the courses offered online, certain challenges arise when teaching computer science (CS) courses to students who are not physically co-located and have individual learning schedules. Teaching CS courses involves high level demonstrations and interactivity between the instructor and students. For example, dropout and failure rate is high in introductory programming classes. Algorithmic thinking is a complex multi-step process. More advanced concepts are layered on top of others which should be learned previously in mathematics and other science areas. The commonly used formats of course contents and methods of communication delivered in distance learning environment such as Microsoft PowerPoint (ppt) and Word, Adobe Portable File Format (PDF), phones or emails are possible to have some level of interactivity. However, better demonstration and interactivity can be achieved by using flash technologies and animated simulations, and employing synchronous communication technology which works as the collaborative platform to allow the instructor and students to have real time application sharing. In this paper, examples of using flash videos and collaborative tools to teach online CS courses are presented. In addition, findings in terms of instructional strategies and suggestions to other educators who may face similar situations to teach online CS courses are discussed.