Math City · Lesson 1
City Hall Training Day
Before they hand you the $125,000 budget, City Hall wants proof you can do planner math. Time to earn your Junior Planner License.
Welcome to City Hall! 🏛️
Every building in a city is really three numbers wearing concrete:
- Floor space = width × depth × number of floors (how much room is inside)
- Capacity = floor space ÷ 25 (each resident needs 25 m² to live comfortably)
- Cost = floor space × $5 (every square meter costs $5 to build)
Master those three and you can design anything — from a cozy cottage to a mega-tower.
Challenge 1: The Building Designer 🏗️
City Hall's test: design a building that houses at least 500 people for $80,000 or less. Drag the sliders and watch your building — and its math — change live. There are many right answers!
Challenge 2: The Doubling Lab 🔬
City Hall's favorite trick question. Start with a small building — 20 × 20 m, 5 floors (2,000 m², 80 people). Press the buttons and watch what doubling does:
Now the exam question: if you double the width AND double the depth, capacity goes up…
Challenge 3: The License Exam 📝
Three questions stand between you and your Junior Planner License.
1. A building is 30 m wide, 20 m deep, with 10 floors. How much floor space?
2. How many people can that same building house (25 m² each)?
3. Which houses MORE people: a wide building 50 × 50 with 4 floors, or a tower 20 × 20 with 30 floors?
🏆 Your XP Progress
- ○ Permit approved (500+ people under $80k) +10 XP
- ○ Cracked the doubling secret +8 XP
- ○ Passed the License Exam +7 XP
Total XP earned: 0 / 25
🖨️ Practice on paper
Download the Planner License Kit — practice buildings to compute, a design-your-own blueprint page, and a license to fill in when you pass.
🧭 Keep Going
🏆 Complete This Lesson!
License in hand? Mark this lesson complete to track your progress.