American Idol’s Best and Worst Moments Ever: Watch Highlights of Kelly Clarkson, Carrie Underwood — and Sanjaya!

Ah, the memories — not to mention a few that would be best not to revisit (no offense, William Hung). American Idol calls it quits on Thursday, April 7, after crowning its season 15 winner, and Us Weekly is taking a look back at the long-running Fox competition series' best and worst moments since its 2002 debut.

No list of Idol highlights is complete without acknowledging some of the countless breathtaking musical performances by its stars-in-the-making over the years, including Kelly Clarkson, Fantasia Barrino, Carrie Underwood, Jennifer Hudson and Adam Lambert.

Another favorite part of the show for many fans was hearing Simon Cowell's biting quips, without which the show might not have succeeded.

Kelly Clarkson
Kelly Clarkson performing on FOX TV's 'American Idol' in 2002. Kevin Winter/ImageDirect/FOX

Of course, the less-exemplary performances often added to the experience as well. Many a watercooler conversation got started over season 6 finalist Sanjaya Malakar's surprising ability to stick around, not to mention his idiosyncratic hairstyles.

Watch some of the show's thrilling highs and cringeworthy lows in the video above.

American Idol's series finale airs on Fox Thursday, April 7, at 8 p.m. ET.

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