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Lesson

6 of 8 in Unit 4: Budgeting

Irregular Expenses

9-12th Grades
45 min

Summary

Some expenses feel like an emergency, but they are actually just irregular. Explore how sinking funds turn predictable irregular expenses into painless monthly line items, and practice the math that makes it work.

Activities

Bellringer: December Surprise

  • Display the holiday gift scenario and give students 1–2 minutes to jot a response.
5 min

Instruction

  • Walk through sinking funds vs. emergency funds, the formula, common irregular expenses, and the emotional payoff of guilt-free spending
10 min

Discussion: Granular vs. Simplifier

  • Split the room into two camps and let them debate whether you should have a sinking fund for everything
  • Close with a vote on which method they'd actually stick with
8 min

Activity: Owning a Car

  • Distribute the Owning a Car worksheet — students explore the irregular expenses associated with car ownership.
  • Circulate and prompt students to connect car-related costs to the sinking fund concept.
15 min

Wrap-Up & Assessment

  • What is the math formula for a sinking fund?
  • Why is a sinking fund not an emergency fund?
7 min

Lesson Prep

Owning a Car Worksheet thumbnail

Owning a Car Worksheet

Students calculate the ongoing costs of car ownership.

Class Presentation

Includes a 16-slide deck with teacher notes. Present from Banzai, download a PDF, or copy it to Google Slides.

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  • Teacher NotesSlide-by-slide guidance, printable as one handout

Unit 4: Budgeting

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