I believe I was in 3rd grade when they played this in my elementary school, but it may have been earlier since Star Wars came out when I was in 1st grade. (LL note: Looks like it was 1st grade. 1977.) I still chuckle when I see this. If the Internet was around back then, they certainly would have had a ton of traffic.
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Apparently, in 1999, George Lucas called Hardware Wars his favorite Star Wars parody.
I'm a big Chewchilla fan myself. I fondly remember him gnawing on Princess Anne-Droid's cinnamon buns.