At the Pierre de Geyter Middle School in St. Denis, a largely Muslim suburb north of Paris, Iannis Roder has taught history for the past 15 years. He says the day after the killings at the magazine, the school staff knew it would have problems.

"Our pupils — a minority — didn't want to do the minute of silence because they thought that Charlie Hebdo was a newspaper that didn't have the right to make these caricatures," says Roder.

Iannis Roder is a history teacher in the largely Muslim suburb of St. Denis, north of Paris. He said some of his students considered the Charlie Hebdo cartoons to be blasphemy and believed that Islam took precedence over French law.

Roder says the students called it blasphemy and he had to explain that blasphemy is a religious concept that doesn't exist in French law.

"That was very difficult to explain because their point of view, their lives, are very religious. And they are convinced that the religion is above the law of the French Republic," he says.

Roder says nearly all the students thought the killings were wrong, but purely for religious reasons. He says he finds that worrisome.