At one point one of the boys brings French magazine "Pilote" which features part of the first "Asterix" comic story and the boys get the idea to scam people into thinking they invented the magic potion from "Asterix". Both "Asterix" and "Le petit Nicholas" where created by Rene Goscinny in 1959. The scam also mimics the scene from the very first Asterix story where Getafix the Druid and Asterix trick the Roman soldiers into thinking they drink the magic potion.
The enervated teacher who tries to get the kids to sing in a choir is played by Gérard Jugnot. He was Clément Mathieu in Les Choristes (2004), a teacher who (successfully) starts a choir in a school for troubled boys.
The poem the class is asked to recite, "Le Corbeau et le Renard" (The Crow and the Fox), is by Jean de La Fontaine (1621-1695). It is based on one of Aesop's fables.
One of the books in Nicolas' room is an abridged version of 'Treasure Island' by Robert Louis Stevenson.
A boy tells Nicolas that his parents are perhaps going to abandon him in the woods like in the 17th century Charles Perrault fairy tale "Le Petit Poucet." (Called "Hop-o'-My-Thumb" in English). In this story, the parents are poor woodcutters and decide they cannot afford to raise their children and they leave them in the forest.