Ann Martin is Caillou's very lovely playschool teacher who debuted in the episode Caillou at daycare. In the episode "A Surprise for Ms. Martin" it is mentioned that her birthday is in June. She has shoulder-length red hair in a neat bun and wears red overalls and a white long-sleeved blouse. There are 12 kids in her playschool class with more joining each season. The original 3: Caillou, Leo and Clementine in Season 1. Jeffery and Jason later joined the class in Season 2, in Season 3 Emma, Mara, Melanie and Xavier started coming, in Season 4, Wendy , Lee-Wun and Allen joined too. She was absent to help her sister with her new baby in "You're Not Ms. Martin!".