ScreenPal, formerly Screencast-O-Matic, is one of the original and most impressive screen recording tools out there. That makes it a great option, specifically tailored to education, for teachers that want a way to record their screens -- and more -- to share with the class.
This can be used on a big screen in the class, across personal devices, and outside the class too -- making teaching more free, while still taking advantage of the digital tools available.
