Schools try to teach at a pace designed to fit a fixed amount of material into a fixed amount of time, and the content is often designed to satisfy some arbitrary goal (such as passing an AP exam). It's an attempt at a one-size-fits-all solution.

Is Perl the best language to teach CS? I don't think so. It's too easy to get sidetracking into nifty features, losing the essense of what's being taught. (C++ isn't any better as a teaching language, though with C++ you're trying to get past the language to solve a problem, as opposed to having lots of ways to solve a problem, each one a bit shorter than the previous.)

Better, I think, to treat Perl as a self-paced, independent study project. Pick a problem to solve that interests you, and learn enough Perl to solve it. Then learn a bit more Perl to solve it better. Then study how others have solved similar problems, and try again. Read articles. (merlyn has some great ones to study on his site.) Learn about benchmarking and profiling, profile your code. Find a good Perl programmer and ask them to review your code. Post it here. Take in the feedback.

That's the way to learn.