The development, the happening, the incident, the occurrence, the situation. The affair, the encounter, the meeting, the moment. the episode, the problem and solution. Others have mentioned these or their ilk: the chapter, the passage, the story, the period, the attack, the bout, the installment, the phase.
That means they use any pronouns so you can call him by any :7
This form of persuasion is ethos. The author is using a credible source, a teacher, to prove that the activity will help students learn. It's important here that her mom is a teacher, if she wasn't, her mom might not be a credible source.
