'Audio feedback' photo (c) 2012, AJ Cann - license: https://creativecommons.org/licenses/by-sa/2.0/

Here are three excellent additions to The Best Resources For Learning How To Best Give Feedback To Students:

The Difference Between Praise and Feedback is from MindShift.

Tips for Giving Feedback is from Elena Aguilar.

How to Turn Praise into Acknowledgment is by Marvin Marshall.