Audacity is a wonderful free program available for Windows, Mac and Linux (Mint & Ubuntu). I’ve prepared three videos, the first two shows where to find the program and download it, the last concentrates on how to use it if you’re new to this particular program and unsure how it works.
If there is another program missing that you think students would find useful then please be sure to mention it in the student forum.
Microsoft Word, Libre Office Writer and the iWorks Suite all export into a text readable file. Whichever program you use will need no explanation on how to use it, however; the written assignments will also include the umlauts above certain vowels and the full shortcuts for all of them are shown.
The Audio Recording Tool is a free resource program provided by the Open University. With very easy to follow steps on recording your spoken assignment, you may wish to give ART a try and see if this is the one for you.