Razor & Tie's Kidz Bop series of singalong collections debuted in 2001. Known for their "kid-friendly" versions of hit singles re-recorded by session musicians and singers and the Kidz Bop Kids, a chorus of child singers, the compilations became popular with families who wanted cleaned-up versions of contemporary songs: beginning with 2005's Kidz Bop, Vol. 7, they routinely debuted within the Billboard Top Ten, and have collectively sold close to ten million copies.nn Along with the expected teen pop fare from Britney Spears, Christina Aguilera, Hilary Duff, and Kelly Clarkson, the early-2000s Kidz Bop installments included more left-of-center picks like Franz Ferdinand's "Do You Want To?" and Modest Mouse's "Float On" as the series evolved. Along with the regular Kidz Bop collections, which were released roughly twice a year, the franchise expanded to include DVDs and collections of oldies, Christmas songs, and Latin pop hits. Kidz Bop also developed ringtones, toys, and a clothing line over the next few years. The Kidz Bop, Vol. 11 album, which featured a cover of Gnarls Barkley's "Crazy" as well as renditions of songs by Justin Timberlake and JoJo, arrived in 2007. Other releases that year included Kidz Bop, Vol. 12 and Coolest Kidz Bop Christmas Ever.nn The series continued releasing albums every few months for the rest of the decade. By the time of 2011's Kidz Bop, Vol. 20, the series emphasized the personalities of the Kidz Bop Kids, who included Steffan, Eva, Elijah, Hanna, and Charisma. The success of subsequent volumes like Kidz Bop, Vol. 31 and Kidz Bop, Vol. 32 -- both released in 2016 -- continued the project's winning streak, which included over 20 albums that debuted in the Billboard Top Ten, regular number ones on the Billboard Kid Albums chart, and many gold certifications. The 2010s also saw a Kidz Bop satellite radio station and a regular live touring company led by Ashlynn, Bredia, Grant, and Matt.nn In 2017, the Kidz Bop Kids continued their successful live schedule with the "Best Time Ever" tour. They also delivered three collections that year, with Kidz Bop 34 featuring selections like Bruno Mars' "24K Magic" and Justin Bieber's "Let Me Love You," and Kidz Bop 36 showcasing up-tempo hits originally by acts like the Chainsmokers, Miley Cyrus, and Calvin Harris. Kidz Bop 37 followed a year later with upbeat versions of songs like Taylor Swift's "Look What You Made Me Do," Camila Cabello's "Havana," Halsey's "Bad at Love," and more. Kidz Bop 38, the second volume to arrive in 2018, featured electronic-pop crossover hits "The Middle" by Zedd and "FRIENDS" by Marshmello, as well as Drake's "God's Plan." The group returned the following year with their 39th volume of covers, featuring versions of songs like Cardi B, Bad Bunny, and J Balvin's "I Like It," 5 Seconds of Summer's "Youngblood," and Drake's meme-worthy "In My Feelings." Kidz Bop 39 debuted at number one on Billboard's Kid Albums chart. ~ Heather Phares