In the current era of technology, why should children write haiku? How can this little Japanese poem be explained to them? The starting point of this paper is quite simple: nowadays, haiku is a widespread genre around the world – including in children’s literature. It is appreciated for its apparent simplicity: a 5-7-5 syllable pattern, a “season word” (kigo) and a cutting word (kireji), that’s all. Far from being a mere hype phenomenon, its present-day popularity has its origins in the first French haiku writers, Paul-Louis Couchoud, René Maublanc and Jean Paulhan, who were fascinated by this form of Japanese poetry in the early 20^th century. This study examines two different corpora (children’s literature and French pioneer vulgarisation), in order to examine one of brevity’s emblematic manifestations.