On Friday she told RTL radio that FN-run councils will ban school canteens from providing alternatives when food that contravenes Muslim and Jewish dietary restrictions is served on the grounds that the move contravenes France's secular constitution.
"We will not accept any religious requirements on school menus," she said. "There is no reason for religion to enter into the public sphere, that's the law."
She accused the mainstream right UMP and the ruling Socialist Party of frequent breaches of laïceté, the French version of secularism that stresses keeping religion out of the public sphere.
In 2006 a court judged that the distribution of pork soup to down-and-outs by members of the far-right Bloc Identitaire was discriminatory and a threat to public order.
In the RTL interview Le Pen also laid into a court in Béthune, northern France, after it fined her 10,000 euros for the distribution of a leaflet purporting to be from hard-left leader Jean-Luc Mélenchon during a by-election in the town of Hénin-Beaumont in 2012.
She had already launched a legal challenge to the court before the trial, she said, "which proves that I knew in advance that the court would not judge this case with impartiality".
The far-right leader has appealed against the judgement.
The case arose from a leaflet with the headline "Vote Mélenchon" in French and incorrectly scripted Arabic, declaring "France has no future with the Arabs and the Berbers of the Maghreb", a quote from a speech the Left Front leader gave in Marseille.
Although the party originally said that sympathisers had produced it, Le Pen later publicly accepted responsibility and on Friday she insisted that it was not a "fake leaflet" but a legitimate part of her campaign.
Mélenchon was squeezed out of the running in the first round of the election and Le Pen eventually lost to the Socialist candidate.
But the FN won control of Hénin-Beaumont local council in the first round of the latest municipal elections.