5 great tools. 4 are free. 3 are production based. 2 are audio. 2 are video. 1 is not like the others.
I teach multi-media production at CSU Fresno, and while many of the tools we use at CSU Fresno are based in Adobe, when it comes to doing my own video production work, these are many of the tools I use. While they may not be the most full featured or most polished, they are reliable and always get the job done right. Audacity is a fantastic audio editor that comes with features that many of the expensive 'pro' software lacks. Soundcloud is best summed up as YouTube for audio. It is a fantastic source for original music and audio hosting (many podcasters use it as a hosting platform). Final Cut Pro X! While many in the professional video industry ditched Final Cut when Apple completely re-wrote the program, I was one of the few who held on and continued to use and learn through the many (and honestly, frustrating changes). A few years in and Final Cut X is the most polished, simple, and full featured post production video programs available. Every good video needs pre-production and a story board is usually a must! Storyboard generator has been put together by the Australian Centre for the Moving Image, and is an amazing tool to teach storyboarding techniques. Last but not least is Flipboard. What may be called an advanced RSS reader, Flipboard is much more! The magazine sharing feature is a great way to share info with fellow educators and students.
Links to all these tools and more can be found HERE