Because of the violent and controversial nature of the film, Toei refused to license it for North American distribution. It also rejected offers from North American companies who wanted to purchase the license of the film.
In the film, the two transfer students are Kiriyama, the silent killer, and Kawada, the winner of a previous Battle Royale. In the original novel, only Kawada was the transfer student; Kiriyama was in the same class selected for this game of death. He was the main antagonist.
In the bungalow, two female students, Hirono and Mitsuko, are having a beef. Hirono taunts Mitsuko, who loses patience and cries out, 'I've had it! Why does everyone gang up on me, what did I do!' In a website dedicated to the film, it states background information [most likely from the manga] that Mitsuko is the 'class slut', hence Hirono's accusations of Mitsuko stealing her boyfriend, among others, is justified.
In the middle and near the end of the film, Kitano is seen and heard conversing with his daughter over the phone; that voice belongs to Maeda Ai, actual older sister of Maeda Aki, who plays Nanahara's girlfriend Noriko.
The Japanese DVD features outtakes from the film. One of these shows that in one scene where a cooking pot is thrown at a girl, the pot actually did hit the actress and hurt her (although not badly). The shot where this happened does appear in the movie, but any sign of her having been hurt was edited out.
In the manga, Utsumi Yukie is described as the class president, hence her reputation of the leader is obvious in the lighthouse scene. Lead character Nanahara Shuya, as the deleted scenes show, is the star basketball athlete, hence his popularity.
www.br.com - emblazoned across the back of the studio during the instructional video - used to be the real website of British Rail, the UK national railway (pre-privatisation).
There is a persistent fallacy about this film that the cutesy announcer who describes the game says "Super Lucky" in classic anime-engrish when picking up an axe. She doesn't. The SUBTITLE reads "This is super lucky", but the announcer speaks an ordinary Japanese phrase.