Walking in straight lines gets us from one place to another in an efficient way. It might not be that fun, but it can be. There are 4 parts to the perfect line, a straight line: 1) is a quiet line, 2) look at the back of the head, 3) no separation, and 4) keep you hands behind your back. If these elements are in a line, it is the perfect line. So we work on making the perfect line on the way to lunch.
"Boys and girls, we will have a straight line to lunch. A straight line is a quiet line. Look at the back of the head of the person in front of you; No separation. Keep your hands behind your back. If we get three strikes we will come all the way back, and therefore, we'll be the last ones to lunch. I don't want to come all the waaaaaaaaaay back, because I'm STARVING! Let's have a perfect line."
A strike is merited if one of the 4 elements is not present. I'll say, "Strike one! Separation." As we proceed through 4 stops, I'll remind students how many strikes we have. We have had to return before. (I'll leave for lunch early if I "feel" like we are going to get three strikes.) Now that's kinda FUN. Don't tell anyone;)