Ahh, yes. We did this too in junior high and high school.

We called it "Ice Blocking." No one quite knew what we meant by it, which was to our advantage.

Watch out for dirt. Before you know it, you will be laying face-down in wet grass wondering what the hell just happened, while your friends laugh so hard that they fall off their blocks as well.

Hint #2:
Adidas shelltoes or some other slick-bottom shoe is preferrable for ultimate speed and control.

Have fun.