The New Zealand Jewish Council says mock Nazi behaviour by Auckland Grammar schoolboys was silly and thoughtless.
Images sent to Radio New Zealand show the students kissing a swastika, making a Nazi salute and kneeling in homage before a Nazi banner.
The photographs, taken at an Auckland War Memorial Museum exhibition marking the 70th anniversary of the beginning of World War II, were posted on the Facebook website (they have since been removed).
Jewish Council president Stephen Goodman says the boys should have known better.
"It trivialises the Holocaust and it trivialises the suffering that people went through," Mr Goodman says, "and it comes down to ignorance, really.
"I don't believe there was any true malicious intent, but anything that trivialises suffering dooms us to repeat history rather than learn from it."
Mr Goodman says he has spoken to Auckland Grammar principal John Morris, and is confident that the matter is being dealt with seriously and professionally.
Mr Morris has told Radio New Zealand that there is absolutely no justification for the boys' immature and unthinking actions, and that they will face appropriate disciplinary action.
Returned and Services' Association president Robin Klitscher told Nine to Noon that the behaviour was offensive and above all profoundly ignorant, while museum spokesperson Karen Mason says staff are shocked and disgusted.
She says they'd like to know whether the students were properly supervised, but also whether the museum can make information about such exhibits clearer.