This was my first screencast using Quicktime, however, my learners and I use Screencastify, a screen capture software for Chrome, very often in the classroom. The main way I have used Screencasts as a tool has been to record myself solving mathematics problems and explaining my reasoning and the strategies I have used to do so. My learners have then been able to use this as a resource when they have trouble answering certain questions.
The learners have been using this tool to record their own thinking when solving mathematics problems. One really useful tool within Screencastify is the ability to draw/write on the screen you are recording. This enables learners to record their thinking live. Used in this way, their recordings become authentic resources they can use later for rewindable learning or even for their peers to use.