A friend of mine earlier forwarded me this panel from the FoxTrot cartoon strip. I can recall considering something like that in a similar situation back when, but decided that (since it is text) it could be done better in perl.

My best guess (which I have attempted to conceal, for those who want to try it themselves) is below, at 70 chars total, but I am by no means a golfing pro-how can it be done better?

perl -e 'print "I will not throw paper airplanes in class.\n" x 500'

Update: Juerd beat me to posting regarding this, but I'd still like to see it golfed....