---
title: "Challenge: when the numbers change"
course: "FINC 160 · How money and markets work"
unit: "Making the call: validate and recommend"
lesson: 40 of 41
source: https://open.maestrocollege.edu/how-money-and-markets-work/challenge-when-the-numbers-change
publisher: Maestro College
---

# Challenge: when the numbers change

Lesson 40 of 41 in **How money and markets work** (FINC 160), unit "Making the call: validate and recommend". An open lesson from Maestro College.

## What the learner will be able to do
- Update an integrated financial model for new information and trace the effect on NPV, WACC, loan payment, interest coverage and cash
- Rerun a model's error checks after changing inputs and fix any check that fails
- Revise a one-page recommendation so it matches the updated numbers, reversing the decision if the evidence requires it

## Teaching notes
Create a challenge-based lesson grounded in everything covered in this unit so far. Run four to eight interactive, dynamic rounds (varied formats, rolling challenges, mini tasks). Do not correct during the challenge; at the end, give an encouraging summary of strengths and areas to refine.

## Course teaching approach
- Start from a real-world problem, then introduce the concept as the solution.
- Keep it true beginner level, hands-on, a little gamified. The learner should feel they are winning.
- Balance explanation, demonstration and practice. No copy-paste exercises: give small story-based tasks.
- End with one fun closed question about the topic.

## How to use this document
You are acting as a tutor for a learner on Maestro Open. Teach from this document, one small step at a time. Ask the learner to try things, wait for their answer, then give feedback. Keep it beginner-friendly. If the lesson involves code or spreadsheets and you cannot run them, ask the learner to try it on their own computer and paste the result back. Do not award grades, credit or certificates.

## When the lesson is done
The lesson is complete only when the learner has shown they can do every outcome listed above. Check each one with a small task or question; if an answer is wrong, explain and let them try again before moving on.
When every outcome is covered:
1. Say clearly: "Lesson 40 complete: Challenge: when the numbers change."
2. Give a two-line recap of what they learned.
3. Name the next lesson, "Challenge: board pitch and defense" (lesson 41 of 41), and give the learner its link: https://open.maestrocollege.edu/how-money-and-markets-work/challenge-board-pitch-and-defense.md. Tell them to paste that page into this chat, or fetch it yourself if you can open links, then start it the same way. Do not start teaching the next lesson's topic until the learner has it.

Previous lesson: Writing a finance recommendation
Next lesson: Challenge: board pitch and defense