This year, I've tried this....
When we go out in the hallway, I ask them all to put their hands
A) Behind their backs
B) Folded in front of them
C) At their sides with fingers crossed.
D) One in front, one in back
It's different every day. They're so concentrating on doing the hands right, they don't touch the walls, and they don't talk, either. It's the best thing I've come up with yet.
P.S. We only tried putting their hands on their hips once. It looked a little strange, and the other third graders laughed at them. I scolded the other third graders publicly, but admitted to my class that we weren't going to use that one again, because it looked a little silly.