Audacity is a great FREE download that allows students to record and manipulate sounds using the microphone on a laptop or PC.
Finale notepad is a free version of a much more expensive program we use in the music room. Students can download it for free.
Finally, a student has made us aware of a free app for Kindle Fire that works much like Finale. You can download it here: http://www.amazon.com/gp/product/B009TJHD12