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Billboard No. 1 Hits: seasons 2, 4, 9
Best: ''Me and Bobby McGee'' by Crystal Bowersox (season 9, winner)
Worst: ''Against All Odds'' by Paige Miles (season 9, eleventh place)
Billboard #1 hits gave the contestants the option of singing a new or old song. Often, the finalists went for tunes that were tried and true. The best was from Crystal Bowersox, whose confident and easygoing take on the classic ''Me And Bobby McGee,'' made famous by Janis Joplin, felt as comfortable as a well-worn slipper. The worst was season 9's Paige Miles, who inexplicably picked the dreaded ''Against All Odds'' and was so pitchy throughout, Simon Cowell said, ''It was like there was five of you singing that song.'' Paige was eliminated the next night.
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Motown: seasons 1, 2, 3, 5 (Stevie), 6 (Diana Ross), 8, 10
Best: ''Let's Get it On'' by Matt Giraud (season 8, fifth place)
Worst: ''You Can't Hurry Love'' by Brandon Rogers (season 6, twelfth place)
Finalists have performed Motown songs in every season of Idol, with only three seasons not featuring a Motown-related theme! So, who sang it best? For my money, season 8's Matt Giraud crooning a sexy ''Let's Get it On'' at the piano can't be beat. The worst is season 6 Idol, Brandon Rogers, totally biffing the words to the Supremes ''You Can't Hurry Love,'' despite mentoring help from Miss Ross herself. Brandon was the first of the top 12 eliminated in his season.
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Country: seasons 2 (country rock), 3, 4, 5, 6, 7 (Dolly Parton), 8 (Opry), 9 (Shania Twain)
Best: ''Always On My Mind'' by Fantasia Barrino (season 3, winner)
Worst: ''Any Man of Mine'' by Siobhan Magnus (season 9, sixth place)
Idol has featured country and related themes every year except season 10. Yes, the year of the country Idols (Scotty McCreery and Lauren Alaina) had no country specific theme! The best country performance was a complete surprise: R&B singer and season 3 winner, Fantasia Barrino proved she could sing the hell out of anything when she put her own heartfelt spin on the country classic, ''You Were Always On My Mind.'' Is that something in my eye? The worst was season 9 chanteuse Siobhan Magnus barreling uncomfortably through ''Any Man of Mine'' on Shania Twain week. Goth girl could wail on the R&B and rock numbers. Country just was not her thing, as her elimination that week proved.
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Standards: seasons 1, 3, 5, 6, 8 (Rat Pack), 9 (Frank Sinatra)
Best: ''Stuff Like That There'' by Kelly Clarkson (season 1, winner)
Worst: ''Blue Skies'' by Casey James (season 9, third place)
Music from the Great American Songbook has given six seasons of contestants the opportunity to stretch musically in ways they may never have before. The best? Season 1 winner Kelly Clarkson became the contestant to beat with a saucy and adorable version of Betty Hutton's ''Stuff Like That There.'' Those vocals were hot! But Casey James' pitchy and strained version of the Irving Berlin classic, ''Blue Skies'' on season 9's Frank Sinatra night was not. Without his guitar, and in front of Harry Connick Jr.'s big band, the bluesy picker seemed totally out of his element.
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Disco: seasons 2, 3, 4 ('70s dance), 6 (Barry Gibb), 8
Best: ''It's Raining Men'' by Kimberly Locke (season 2, third place)
Worst: ''Celebration'' by Josh Gracin (season 2, fourth place)
Disco is harder to sing than it seems and has brought many a good Idol down. Maybe that's why there hasn't been a Disco theme since season 8. Season 2's Kimberley Locke cemented her future as club queen when she belted out an absolutely fabulous version of the camp classic ''It's Raining Men.'' Maybe it was the scary hairdo that turned off voters. The worst was Josh Gracin, Kimberly's cast mate, country crooner, and Marine, who attempted to get dancey with Kool and the Gang's ''Celebration.'' The song just doesn't work with a twang, y'all. It also would have helped if Josh had sung it in tune.
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Songs of the Cinema/Movies: seasons 2, 3, 7, 8, 9, 10
Best: ''Falling Slowly'' by Kris Allen (season 8, winner)
Worst: ''Against All Odds'' by Corey Clark (season 2, disqualified)
It's not just movie tunes that qualify for movie week—a theme that's been done six times on Idol—any song that has appeared for any reason in a movie counts, making some of the song selections pretty random. The best one came from soulful crooner Kris Allen. The season 8 winner sang Glen Hansard and Markéta Irglová's Oscar-winning song, ''Falling Slowly,'' from the movie Once. Allen's exquisite and moving performance, complete with acoustic guitar, seemed to stop time in the hushed Idoldome. The worst was Corey Clark on season 2, who would eventually be disqualified for failing to disclose some legal troubles to the producers. Corey's off-key falsetto must have had doggies and kitties howling in pain at the TV. This was the first tragic version of ''Against All Odds'' on Idol, but it would not be the last. Please Idol producers: Retire this one already!
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Year They Were Born: seasons 4, 5, 8, 10
Best: ''Mad World'' by Adam Lambert (season 8, runner-up)
Worst: ''Smells Like Teen Spirit'' by Casey Abrams (season 10, sixth place)
In earlier seasons, the Year They Were Born theme used to be a '70s and '80s fest. Now, after 10 years, and the age limit lowered to 15, you've got your '90s tunes represented. The best of this theme has got to be Adam Lambert's haunting version of Tears for Fears' 1982 hit, ''Mad World.'' The season 8 runner-up performed the slowed-up Gary Jules version in a setting that featured Adam, a chair, and his incredible powerhouse vocals. The worst was from 1991 baby Casey Abrams, who set aside his usual jazz stylings and strapped on an electric bass to sing a shouty, confusing version of Nirvana's ''Smells Like Teen Spirit.'' The season 10 Idol should never have ditched his upright bass.
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Songs of Inspiration: seasons 6, 7, 9, 10
Best: ''Somewhere Over the Rainbow'' by Jason Castro (season 7, fourth place)
Worst: ''Better Days'' by Tim Urban (season 9, seventh place)
The first Songs of Inspiration theme was for the season 6 special, Idols Give Back and became the theme for subsequent season 7 and season 9 installments of the fund-raiser. The best performance was the simplest. It was the Israel Kamakawiwo'ole version of ''Over the Rainbow'' that Jason Castro, season 7's dread head, chose to sing. On the ukulele, Jason's plaintive vocal and simple arrangement combined to create one of season 7's major moments. The worst was Tim Urban, who had his heart in the right place, but the Goo Goo Dolls ''Better Days'' proved to be way too big a song for the season 9 contestant's limited vocals. He was pitchy all over the place, and out the door the next night.
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Rock: seasons 5 (Queen, Elvis), 6 (Bon Jovi), 7 (Hall of Fame), 8 (classic rock), 9 (Elvis), 10 (Hall of Fame)
Best: ''Slow Ride'' by Adam Lambert (season 8, runner-up) and Allison Iraheta (season 8, fourth place)
Worst: ''Dream On'' by Danny Gokey (season 8, third place)
A rock theme on American Idol takes many forms—from the Rock Hall of Fame (which was done twice) to individual treatments of Elvis and Queen. But it was the night Idol did a Classic Rock theme with Slash on guitar in season 8 that produced the best and worst performances. The winner was a scorching duet between glamtastic Adam Lambert and the redheaded rocker Allison Iraheta. Not only were the vocals spot on, but the fun the two pals were obviously having on stage was positively infectious. The worst was Danny Gokey's ''Dream On,'' featuring the scream heard round the world. Danny was performing the Aerosmith tune passably until he attempted to end the song with Steven Tyler's killer high note. Needless to say, he didn't hit it. The scary sound emitting from the third-place finisher was not human. That's all I'm saying.
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British Invasion: seasons 7 (Beatles x2), 6 (British Invasion), 9 (Beatles, Stones)
Best: ''I Who Have Nothing'' by Jordin Sparks (season 6, winner)
Worst: ''Eight Days a Week'' by Kristy Lee Cook (season 7, seventh place)
The Brits who run Idol have featured the music of their fellow countrymen and -women on several occasions. The best was Jordin Sparks' emotional and mature-beyond-her-years take on Shirley Bassey's ''I Who Have Nothing.'' The season 6 Idol winner proved she had the vocal chops to compete with the boys during that season's British Invasion week. The worst was Kristy Lee Cook's country-fried version of the Beatles' ''Eight Days a Week.'' Who thought that bluegrass Beatles on speed was a good idea? It was not.