HOW DO YOU CREATE A SUCESSFULL OFFENSIVE LINE?

I help coach 7 th grade lineman. Our boys range from 140lbs to 200lbs. We had a lot odf problems with some of the bigger boys not being quick enough to get their blocks on pass plays. We have had good luck with what the boys call the "candy bar" drill. We place a stand up blocking dummy 7 yds behind the line of scrimmage with a football on top. Each offensive lineman goes one on one against the other linemen and try to keep them from touching the football for 6 seconds. In our team case, the boys go for seven plays straight. The boy who keeps the most kids out wins a candy bar. It has worked wonders on our pass blocking particularly sustaining the blocks . It also helps the defensive lineman to get in to the QB. The kids love it and beg to do it.