How to Perform the Squat - Proper Squats Form & Technique
Proper squat technique
Attached is the proper way to complete a squat, please review the video and compare your personal squat to the video.
Adobe for academics is a great site that can be used to give audio feedback, I have not used this site yet but after researching the site I plan on using it often.
Goanimate.com is a fun way to give visual feedback to students, you can use different characters and backgrouonds as well.