Try a Semi-Circle Instead

Hank Nash, a teacher at South Kitsap High School in Port Orchard Washington

I never have students line up in a straight line before entering the room. Instead, I have them line up in a semi-circle facing the door. That way, right when I open the door, I can see all of the students' faces, what they are wearing, and can greet them all at the same time. I never have to worry about getting the attention of the back of the line.