Lastly, I completely disagree with the use of log files for teaching elementary Perl. Simple data constructs, variable assignment, string manipulation, simple regexes, debugging and getting Perl installled/running are topics of primary importance because they must be used all the time. Parsing large files is not something you will do all of the time, and therefore should not be promoted too early any more than the use of sockets
Depends entirely upon the audience and lesson preparation,
and what you're trying to learn, to wit,
Seven Levels of Perl Mastery,
Ten Perl Myths, Modern Perl Released as Free ePub
Pick your path to mastery, the long road, Seven Levels; the short,
Modern Perl.