Designing a Better World, One City at a Time
Inside the Sixth Grade Green City Design Challenge
BY MELISSA ULSAKER MAAS ’76
What makes a city a good place to live?
It’s a deceptively simple question and one that our sixth graders spend months trying to answer. Not in theory, but in practice.
In the Green City Design Challenge, students take on the role of urban planners, designing cities set in real-world locations across the globe. Working in teams, they build from the ground up—housing, transportation systems, energy sources, public services—making hundreds of decisions along the way. Every choice has consequences. Every system is connected. And nothing is unlimited.
“It’s not just about building a city,” says Middle School Science Teacher Alex Mooskin. “It’s about understanding how all the pieces work together—and what happens when they don’t.”
The project has evolved significantly since its early beginnings. Alex first developed the idea in 2015 as part of a Japan-U.S. teacher exchange program focused on education for sustainable development. What began as a more contained, paper-based assignment has grown into a dynamic, tech-driven experience. Today, students design their cities digitally, using detailed maps, building systems, and budget tools that mirror real-world constraints and tradeoffs.
The premise is straightforward: each team selects a real-world location—one of 28 options spanning different climates, geographies, and resource conditions—and designs a city that could realistically exist there. But the simplicity ends there.
Students must research their location carefully. Is solar energy viable? Are earthquakes or floods a concern? What natural resources are available and what’s limited? Those answers shape everything that follows.
From there, teams begin building. They choose how to generate energy, how to manage water and waste, how people will get around, and how land will be used. They decide where to place schools, hospitals, parks, and housing. They determine how dense their city will be and who it will serve.
And then there’s the budget.
Every building, system, and service comes with both upfront and ongoing costs, tracked in a shared spreadsheet. While there’s no strict cap, students know their final budget will be displayed alongside their city, so excess has consequences. The result is a constant balancing act between ambition and reality.
“Students come in with big ideas,” Alex says. “And then pretty quickly, they realize they can’t do everything. They have to prioritize and justify why.”
That tension—between what’s ideal and what’s possible—is at the heart of the project.
Alongside cost, students are also evaluated on two key measures: a “green grade,” which reflects environmental sustainability, and an “equity score,” which measures how well their city serves its population. Are resources distributed fairly? Can residents access what they need? Are there enough schools, public services, and transportation options and are they reachable?
These aren’t abstract questions. Students test their designs by stepping into the lives of fictional residents, each with different needs, incomes, and daily routines. A city that looks good on paper may not function well for everyone and students are pushed to confront that reality.
“That perspective-taking piece is huge,” Alex explains. “It’s one thing to say a city should be equitable. It’s much harder to actually design one that is.”
At the same time, the project pushes students to think about the human side of cities. They consider access to public services, the placement of schools and hospitals, and how to support different populations—decisions that ultimately shape whether a city feels livable and equitable. It’s a reminder that designing a city isn’t just about systems, but about the people those systems serve.
“They’re thinking about both sides at the same time,” Alex says. “A city has to work environmentally, but it also has to work for the people who live there.”
Throughout the process, students revisit and revise their work, responding to feedback from peers and teachers. They also complete individual components that deepen their thinking. Each student designs a landmark for their city—something that improves quality of life while also benefiting the environment and writes a newspaper article about a natural disaster that affects their location. The twist: the severity of the disaster depends on how much their team chose to invest in preparedness ahead of time.
It’s another lesson in consequences, and in foresight.
By the end of the project, each team has created a fully developed city, complete with a detailed map, budget, sustainability metrics, and a clear set of priorities. But the work doesn’t stay on paper (or screen).
The challenge culminates in a public exhibition for families, faculty, and staff, where students present a full display of their city. This includes their completed map, final budget, equity score and green grade, and the UN Sustainable Development Goals they chose to prioritize. To organize their thinking and communicate their ideas clearly, each student prepares speaking notes in advance.
It’s a moment that reveals just how much they’ve absorbed.
“They start to realize how complex cities really are,” Alex says. “There’s no perfect solution. Every decision involves tradeoffs.”
That realization may be the most important outcome of all.
Beyond the content knowledge—science concepts, research skills, mathematical thinking—students leave with something harder to quantify: a deeper awareness of the world around them, and their place within it.
They begin to notice the design of their own communities. The placement of roads. The availability of parks. The accessibility of services. Things that once felt invisible become visible and meaningful.
More importantly, they begin to see themselves as capable of shaping those environments.
“If they walk away understanding how their surroundings influence the way people live and feeling like they can make those systems better, then the project has done its job.”