Classroom activity Grade 12 Social Studies & Civics
Ambleford's Water Capital Budget Challenge: A Grade 12 Activity
A grade 12 economics activity where student teams choose a fictional city's water projects under a fixed capital budget, then adjust when federal mandates take priority.
Objectives
- Students will build a water capital portfolio that stays within a fixed budget.
- Students will justify project choices using marginal cost and benefit reasoning.
- Students will explain how a federal mandate constrains a city's budget choices.
Vocabulary
Key words: capital budget, opportunity cost, marginal benefit, mandate, prioritization, trade-off
Teacher overview
A city never has enough money to fix everything at once, so its water department must rank projects and fund the most important ones first. This activity gives student teams that job for the fictional city of Ambleford, which has a fixed capital budget and a menu of water projects that together cost far more than the budget allows. Teams build a portfolio, defend it with cost-and-benefit reasoning, and then face a twist: two projects turn out to be legally required, showing how a federal mandate can shrink the room a city has to make its own choices. Groups of four work best.
Activity Directions
- Before class, print the project menu cards from the Student Handout and prepare a simple budget worksheet with columns for project, cost, running total, and reasoning. Arrange desks for teams of four. Each team is the water department of the fictional city of Ambleford, with a capital budget of $10 million for this cycle.
- Setup (5 min): Read the situation. Ambleford has six candidate water projects. Their costs add up to $17 million, but the budget is only $10 million, so no team can fund everything. Review the six cards so every team understands each project's cost and benefit.
- Round one, free choice (15 min): Each team selects a portfolio of projects that stays at or below $10 million. On chart paper, teams list the projects they funded, the total cost, and one sentence of reasoning for each choice. Encourage teams to compare the benefit of a project against its cost rather than simply picking the cheapest options.
- Round two, the mandate (15 min): Announce the twist. Two projects, the PFAS treatment and the lead service line replacement, are now required by federal rule, so every team must fund both. This leaves only $2 million for the remaining four projects. Teams revise their portfolios and note which projects they had to drop.
- Gallery walk and share (15 min): Teams post their round-two charts. Each team explains, in one minute, which project it cut and why, and whether the mandate forced a choice it disagreed with.
- Debrief (10 min): Close with the debrief questions below, drawing out how marginal reasoning guided the first round and how the mandate changed the second.
Student Handout
The six projects for the fictional city of Ambleford. Your capital budget is $10 million.
Project A, Replace aging cast-iron mains: $4 million. Five miles of century-old pipe break often; replacing them prevents costly emergency repairs and water loss.
Project B, Lead service line replacement: $3 million. Replaces lead pipes in the oldest neighborhood, protecting children from lead exposure.
Project C, PFAS treatment for the well field: $5 million. Installs granular activated carbon so the water meets the new federal PFAS limit.
Project D, New elevated storage tank: $2 million. Improves water pressure and fire flow for the growing north side.
Project E, Citywide smart meters: $2 million. Detects leaks and improves billing accuracy, reducing lost water and lost revenue.
Project F, Green stormwater pilot: $1 million. Rain gardens and permeable pavement reduce street flooding downtown.
Record your funded projects, the running total, and your reasoning on the budget worksheet. In round two, Projects B and C are required and must be funded first.
Debrief questions. Answer all three after the gallery walk.
In round one, how did you decide which projects to fund first?
In round two, Project B costs $3 million and Project C costs $5 million, and both are required out of your $10 million capital budget. How much of the budget is left for the other four projects?
How did the federal mandate change the city's choices?
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
- Answer: Answers will vary by team.
Debrief question 1: strong teams compared each project's benefit against its cost, funding high-benefit projects such as main replacement or lead removal before lower-benefit options, rather than only choosing the cheapest projects to fit more in. - Answer: $2 million.
Debrief question 2: after the mandate, Projects B and C used $8 million of the $10 million budget. Only $2 million remained, so teams could fund only one of Projects D, E, or F, since the cheapest pair still costs $3 million, and had to cut the rest, including the $4 million main replacement. - Answer: It removed the city's discretion over its own priorities.
Debrief question 3: the mandate removed discretion by forcing two projects to the top, so the city's own priorities competed for a much smaller share of the budget, showing how higher-level rules constrain local decisions.
Differentiation
Support
Give students a budget worksheet with a running-total column and the round-two required projects already entered, so they can focus on the trade-off reasoning for the remaining money rather than on tracking the arithmetic.
Extension
Ask a team to propose how Ambleford could fund one project it was forced to cut, such as phasing it over two budget cycles or issuing a bond, and to explain the trade-off that financing choice creates.
ELL supports
Pre-teach "budget," "mandate," "trade-off," and "priority" with the project cards and simple cost icons. Provide a sentence frame for the reasoning column, such as "We funded Project ___ because its benefit is ___," and allow teams to present their gallery chart together.