Squat jumpy thing

So in my adv. body condt. class on Wednesday we did what I like to call squat jumpy things.
We faced the mirrors, squated all the way down and then jumped high, touched our hands to the mirror and then back down. We did three sets. I did maybe 5-6 in each set–that was all I could do before feeling like I was going to fall over. My legs were shaking for the rest of the class. And my thighs were sore yesterday and oh man, they are hurting more today. (So at least I know it was good, right?)
I found a couple of links that kinda describe the exercise:
This link shows pretty much how low we went.
This link explains the exercise with a higher squat and no mirror involvement.