The first word was eaten by a cow!

All Sunday long, Nikita struggles with his homework and the poem he was assigned to memorize. Out of boredom, he draws a cow in his literature textbook. The boy has no idea that the cow will turn out to be magical and begin to eat words from books belonging not only to Nikita but also to his friends. Will the fourth graders manage to solve the mystery of the mysteriously disappearing texts?