I am always very impressed by kids in marching bands. It's hard work! I did it for a year and just wasn't very good at it.
I am one of those people who can't walk and chew gum at the same time, so I'd probably be terrible at it! Fortunately, my high school did not have a marching band, so I never had to try.
Just found this clip of my daughters' marching band from last year. They are not nearly as polished as the band in the clip Barry posted (not even close), but thought I'd share it anyway. After 30 seconds, they actually DO start marching.