Other and more intelligent reviewers have already mentioned it as well, and I can only concur. "School of Death" (original title: "El Colegio de la Muerte") tries really hard to look a lot like that other Spanish cult classic "The House that Screamed" (original title: "La Residencia"). Hey, I don't blame the makers, because the 1969 landmark by Narciso Ibáñez-Serrador still is and will forever remain one of the greatest European horror movies ever made. But I also admire co-writer/director Pedro Ramirez for his effort, especially since "School of Death" mixes gothic horror with sleaze and mystery elements that were typical for Krimi-thrillers based on the work of Edgar Wallace.
The story takes place in the year 1899 in London, in an orphanage/institute for young girls run by the strict headmistress Wilkins. She allegedly finds deeply Catholic and God-fearing foster families for her girls, but the disturbing reality is they're being lobotomized by a psychotic doctor (whose scarred face looks like a national Spanish dish of paella) first, and then introduced in a sleazy prostitution network. The lovely Leonore seeks for help when she stumbles into her previous roommate Sylvia, but the latter doesn't recognize her, and walks by like a zombie.
Granted, the glorious heydays of goth-horror with mad & deformed scientists and Victorian damsels in distress were perhaps long finished in 1975, but "School of Death" is nevertheless a fun and morbid piece of Spanish horror. It's often atmospheric, for instance the sequences at the cemetery or when Sylvia is transported in a creepy carriage around London at night, and there are a few bloody murder scenes. The script serves several "surprise"-twists in the finale, of which some are very good, and others are either silly or predictable. Overall, though, "School of Death" is a cool and warmly recommended mid-70s Euro-horror flick.