Both are definitely bad movies and insulting to their original source material. Bratz has racial stereotypes, characters that are made paper-thin, is a rip-off of Mean Girls, Yasmin (Who is supposed to be Latina) and Jade (Who is supposed to be Asian) are played by women that are only half their ethnicity and half white so they can be aesthetically pleasing to the caucasian expectations, a lot of terrible pop songs (Not all though, since Rockstar was pretty entertaining), having Yasmin's mother or grandmother (I don't know) not even played by a Latina but instead played by a Jewish woman, and while the message it was trying to have was good it's done POORLY!

However, Jem and the Holograms is the FAR WORSE and INSULTING movie! Bratz: The Movie did have the four main characters KIND OF have A LITTLE chemistry to where their friendship is SOMEWHAT believable TO AN EXTENT. Besides, it gave us something that at least is SOMEWHAT believable as resembling the Bratz where as this movie has absolutely NOTHING resembling Jem other than the names of the characters and the movie. I mean, if you look at this movie and then look at a picture of the show, it's absolutely UNRECOGNIZABLE! Bratz: The Movie at least kind of has the Bratz, this movie has absolutely NO JEM!

Bratz is at least a forgettable bad movie, whereas Jem and the Holograms is one of my top 20 WORST movies I've ever seen! It was so bad that it was pulled from theaters after only two weeks and in some areas didn't even make it to theaters and was put to direct-to-DVD. Both movies were despised by fans of the original product but this movie is even more insulting and here is a two and a half minute clip from the Nostalgia Critic's review of the movie to explain why. Let me tell you, it was like manipulating fans saying how much they love Avatar: The Last Airbender and make it look like they're talking about the universally despised live-action The Last Airbender movie. That's right, it's THAT INSULTING!

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Both are absolutely atrocious and top-15-worst-movies-of-all-time worthy material. Jem has bad characters, is cheaply made, and is more of a montage of YouTube videos than an actual movie, but Bratz... the characters are stupid and shallow, the Asian and Hispanic stereotypes are ridiculous and headache-inducing, the "plot" is abhorrent, the songs are TERRIBLE, the villain doesn't even have a motivation to segregate (speaking of which, does this movie take place in the reality where Hitler won the war?) all the students, the whole movie is nothing but product placement ("I LOVE MYSPACE"), the actors don't even try, and Jon Voight and Anneliese van der Pol don't belong in this trash.
Don't even get me started on Nathalia Ramos' (Yasmin) godawful acting. I thought she was a terrible actress on House of Anubis (though I did like her character, Nina), but this movie just proves she's a terrible actress overall.