When the scoreboard for the State Championship is shown at the end of the 3rd set, the scores at the bottom for the 1st two sets are wrong.
Caroline Found actually died August 11, 2011 two weeks before the school year began, not during the first week of as shown in a film.
A number of times, the word "game" is incorrectly used rather than the proper "match" when West is playing or will play an opponent. A volleyball match consists of games and the team that wins three games wins the match.
In the movie the claimed the Trojans had to win 15 games in a row to qualify for state. This is incorrect. In Iowa, for the first round of playoffs every single team is entered into a bracket, even if they have never won a game.
In multiple games, including ones not set in the Trojans' gym, the same extra, wearing a yellow Star Trek Starfleet shirt, can be seen.
The flag in the Trojans' gym is a 48-star American flag from before Alaska and Hawaii became states. By comparison, the flag at the end of the film during the "State" match has the full, proper 50-star arrangement.
Many of the songs featured in the film did not exist in 2011 when the film is set. "Confident" by Demi Lovato wasn't released until 2015, and "Roar" by Katy Perry wasn't released until 2013.
Caroline and Kelley are shown singing along to Katy Perry's Roar; the song was released in 2013, two years after the incidents depicted in the movie.
The opening scene shows mountains in the background. The Iowa City/Cedar Rapids area has rolling hills, but not mountains.
In one radio/TV announcement, the Iowa station call letters are WKRG, but later there is footage from KCRG. KCRG is correct, but there would be no stations operating out of Iowa with call letters starting with W. The state is on the west side of the Mississippi. States on the east side of the Mississippi River have stations with call letters starting with W. States on the west side of the Mississippi River have stations with call letters starting with K.