Teach programming in C# and basic game development. Unity is offering their course for free for the next three months. They have instructors teaching virtual hour online classes.
Zoom Video Conferencing- create a online meeting space where you can share your screen, see your pupils and engage in conversation. Free for 40 minutes at a time. https://zoom.us/
PowerPoint has an option that allows teachers to record over the presentation and then save it as a mp4. This could be great for supplementing dissemination of materials