The Simpsons (1989): Season 25, Episode 19

25 - 19: What to Expect When Bart's Expecting

Bart can't stand art class. So he makes a voodoo doll of his art teacher. But when his spell makes her pregnant instead, he becomes a savior to Springfield couples trying to conceive. Then, he's kidnapped to help conceive a thoroughbred race horse. Blackboard 'You can't play April Fool's jokes on April 27th'.