Here's why:
* Direct Object: The direct object is the thing that receives the action of the verb. In this case, the direct object is "story" because the teacher is telling the story.
* Indirect Object: The indirect object is the person or thing that is indirectly affected by the verb. In this case, the class is the indirect recipient of the story. The teacher is telling the story to the class.
You can often identify an indirect object by asking "to whom?" or "for whom?" the action is performed. In this case, you can ask "To whom did the teacher tell the story?" The answer is "class".