These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Clarissa Explains It All
Ear Worm: If you listen, you might as well not even try to get the "Na na na na" theme out of your head.
"Funny Aneurysm" Moment: "Being an understudy is like being Princess Di: lots of fringe benefits and no drawbacks!"
Mindless Self Indulgence has a song called "Clarissa," which includes the classic line "If you're so smart, explain this, Clarissa!"
Another band called The Paramedic has a song called "Clarissa Didn't Explain This," which in all actuality has absolutely nothing to do with the show.
Even Melissa Joan Hart herself makes a play on the show's title in the title of her autobiography, "Melissa Explains It All."
Unintentionally Unsympathetic: While most of her problems with Ferguson were pretty valid, there were a couple instances where she seemed like a bully. For example, in one episode, Ferguson seeks her for advice on how to properly date a girl he has a crush on. She deliberately gives him the most outlandish suggestions she can think of to sabotage his relationship with her. Granted, this backfires, but it's still a pretty mean and bullish thing to do.