S5·E60 You're Not Miss Martin!

Caillou isnt too happy when Miss Martin is away and his preschool class has a substitute teacher Mrs. Shelley. She does everything differently and isnt familiar with the usual routines. When Caillou tries to see things from Mrs. Shelleys perspective, he decides to give her another chance... only to realize how wonderful Mrs. Shelley really is... even if she isnt Miss Martin.