It was a moving portrayal of everyday life in the rural classroom, and became an huge and unexpected French cinema success when it was released in 2002.
And, as the star of the prizewinning documentary film, Etre et Avoir, Georges Lopez felt it was only fair that he should get a cut of the €2m (£1.3m) profits.
The director disagreed, triggering an acrimonious lawsuit which has raised uncomfortable ethical questions about the exploitative nature of fly-on-the-wall film-making.
This week a Paris court ruled that the schoolteacher, who allowed his tiny one-class village school to be filmed in lessons and at play over the course of a year, had no grounds to demand a €250,000 (£170,000) payment.
Insistent that his rights had been abused, Mr Lopez said yesterday that he would appeal.
Had Mr Lopez won, French film unions warned, the case would "spell the death of the documentary, undermining the crucial principle that subjects should not be paid to participate."
Mr Lopez's decision to sue the documentary's makers for a healthy share of the profits soured the popular image of him as a modest, selfless schoolmaster.
But he claimed that the film's success rested entirely on his personality, and that his teaching methods, made famous by the film, were his intellectual property.
Mr Lopez said he felt exploited, and launched the legal suit in the face of "lack of respect shown by the cinema world".
He refused a one-off payment offered by the documentary makers of €37,500, insisting he should be treated like an "actor" in the film and be properly remunerated.
A court in Paris ruled that Mr Lopez deserved no payment for taking part in the project.
In a judgment which analysed what constitutes a documentary, the court decided that the teacher had no grounds to argue that he should be treated as an actor because he was filmed as he went about his everyday professional duties.
The court also found he had given consent for his image to be exploited in accepting to be filmed.
Mr Lopez could not be considered a "co-author" of the film because he had not taken part in decisions on how to shoot the documentary.
"The film revealed the great professional skill of the teacher, his thoughts on his profession and the effectiveness of his teaching methods," the court ruled, but none of these were "qualities that could be protected by intellectual property legislation".
French film-making unions were relieved. The Association of French Film-makers said: "The nature and the economics of documentary are incompatible with any principle of remuneration."
The film's director, Nicolas Philibert, visited around 300 schools before selecting the classroom in the village of Saint-Etienne-sur-Esson, Auvergne, where he was impressed by Mr Lopez's dedication and deep attachment to his pupils.
After the film came out, the prime minister, Jean-Pierre Raffarin, requested a private viewing.
Philibert spent seven months filming Mr Lopez, 58, for Etre et Avoir (named after the two key French verbs, meaning to be and to have), and admitted feeling "very hurt and deeply distressed" by the legal action, which he viewed as a "betrayal".
French newspapers agreed, reporting the initial claim beneath the headline: "To be and to have: the teacher would rather have."
Claire Hocquet, who represented Philibert, said after the ruling: "I am delighted the tribunal ruled that reality should not be paid for."
She added: "To pay someone who appears in a documentary would be to treat them as an actor, and that would be the death of documentary film-making."
But the legal dispute over the film's profits is to continue later this year, when the families of seven of Mr Lopez's 11 pupils are going to court to seek payment of €20,000 each for their parts in it.