PROJECTILE WAR — From Physics Classroom to Production-Ready Duel
Guillermo Ithier • Physics Teacher / Game Designer
Ridgefield Park Junior/Senior High School • 11th Grade Physics
Version 2.0 Final (2025-11-02) • Production Ready
The one-line pitch
I designed PROJECTILE WAR as a fast, competitive artillery duel that turns physics thinking into tactical decision-making: players trade tempo for safety as each cannon accumulates Stress (σ), pushing the system until it cracks—or stabilizing just long enough to win.
Problem
I wanted a classroom-ready game that could do three things at once:
- Make physics feel operational, not theoretical—students should use relationships like force and acceleration rather than only solve for them.
- Run inside a real block schedule—setup + teach + multiple matches + reflection in a single 85-minute period.
- Stay genuinely competitive—if it felt like “educational medicine,” students would disengage.
The key constraint: it had to be learnable fast, playable repeatedly, and deep enough that students improved across matches.
Design Goal
Build a tactical duel that teaches risk management the way physics systems demand it:
- Push harder → gain output → increase system strain
- Play safe → preserve system integrity → lose tempo
That became the core fantasy and the core mechanic: “Command your artillery. Manage the chaos.”
Solution Overview
PROJECTILE WAR is a 2-player card-based artillery duel built on three interlocking ideas:
1) Physics as a legality filter (not a lecture)
Every offensive card is a projectile with three readable stats:
- M (Mass)
- A (Acceleration)
- F (Force Threshold)
A shot is legal only if: M × A ≥ F
This does two things instantly:
- It makes “physics thinking” a gate to action (students self-check before playing).
- It keeps the rules transparent: players know why a shot is or isn’t valid.
2) Stress creates strategy (three cannons = rotation puzzle)
Each player has 3 cannons, and each cannon tracks Stress (σ) independently. Firing builds σ—keep pushing and you risk detonation. This creates:
- planned rotation (don’t overheat one cannon)
- deliberate overheat windows (sometimes you should push)
- an emergent tempo metagame (when to stabilize vs. when to break shields)
3) Maintenance is unified (one elegant choice, constant tension)
Instead of separate “repair categories,” I used General Maintenance cards:
When played, you must choose Shield Support or Cannon Support.
This is the heart of the game’s decision-making:
- If you stabilize cannons, you preserve long-term firing capacity
- If you support shields, you survive the next wave
- Either way, you sacrifice tempo—so the choice always matters
Design Snapshot
- Players: 2
- Length: 10–12 minutes
- Complexity: Medium (easy to learn, difficult to master)
- Components: 49 cards, 3 cannons + 2 shields per player, σ markers, Φ tracker, 2d6
Card mix (designed for scarcity and timing):
- 38 Offensive
- 8 Maintenance (dual-purpose)
- 3 Utility (Aim, Reroll, Overhaul)
Why 2d6
I chose 2d6 deliberately because the probability curve is teachable and feelable. Students quickly learn that outcomes cluster near the middle, which supports:
- planning
- risk estimation
- meaningful “push vs. reset” choices as σ increases
It also supports the classroom: the game becomes skillful quickly, not random-feeling.
Classroom Implementation (85-minute block)
Environment: Ridgefield Park Jr/Sr HS — 11th Grade Physics
Format: Rapid teach → supervised play → independent play → debrief
Block schedule protocol
0–5 min — Setup & distribution
Decks and tokens handed out, pairs assigned, play space cleared.
5–17 min — Teach + first-turn demo
I taught:
- the core loop (Fire / Maintenance / Utility)
- the legality rule (M × A ≥ F)
- what σ and Φ represent (system strain and degradation pressure)
Then I ran one complete “model turn” with explicit updates and redraw.
17–35 min — Supervised matches
Students played with me actively circulating, tracking:
- confusion points
- illegal plays
- pace vs the 10–12 minute target
- whether players rotated cannons or tunneled one “favorite” cannon
35–70 min — Independent repeat matches
Students ran multiple games with minimal intervention. My observation targets:
- tempo vs stabilization decisions
- Maintenance timing
- endgame clarity (did players see when they were losing?)
- whether degradation systems prevented stalling
70–80 min — Debrief + quick survey
Short prompts:
- clarity
- fun
- perceived agency
- most confusing rule
- suggested improvements
80–85 min — Pack-up & design notes
Collected materials and consolidated iteration decisions.
What I Measured (and why it matters)
I treated the classroom like a live usability lab. I focused on signals that correlate strongly with real-world tabletop success:
- Learnability: time to first legal action; repeated questions
- Pace: match length vs target
- Decision quality: cannon rotation frequency; Maintenance timing; willingness to push at higher σ
- Clarity: which terms/rules repeatedly broke flow (σ, Φ, legality, damage flow)
- Balance signals: shield break patterns; cannon losses; runaway leads vs comeback viability
Key Findings
Two friction points emerged consistently:
Friction #1 — Players delayed the Maintenance choice
Students would play Maintenance, then pause, trying to decide later whether it was Shield Support or Cannon Support. That created table stoppages and uncertainty.
Fix:
Maintenance now requires choosing its mode immediately when played.
Friction #2 — Players forgot σ/Φ updates during fast turns
The game’s pace was a success—but speed caused missed bookkeeping, especially late-game.
Fix:
I redesigned the reference sheet to include a tight end-of-turn checklist:
Update σ/Φ → Apply damage/HP → Discard → Draw to 5
These changes reduced interruptions without weakening the “push vs stabilize” tension.
Outcome
By Version 2.0 Final:
- The core loop stayed stable across supervised and independent play.
- Students completed multiple matches within one 85-minute block, including teach and debrief.
- The game consistently produced the intended arc:
- early probing fire
- mid-game rotation and Maintenance windows
- endgame forced by degradation pressure (anti-stall entropy)
Most importantly: the classroom wasn’t just a testing venue—it was a proof that the design could survive real-world constraints: limited time, mixed skill levels, and high cognitive load.
What This Project Demonstrates (Portfolio Value)
As a designer:
- I can build a system around a single dominant tension and keep it clean.
- I can design mechanics that are both thematic and functional (physics as action gating).
- I iterate based on observed friction, not instinct.
As a teacher-designer:
- I can run structured playtests with adolescents, capture usable data, and turn it into targeted rule revisions.
- I can make learning emergent—students practice arithmetic, estimation, probability intuition, and systems thinking because winning demands it.
Deliverables Available on Request
- Full card list and tuning tables
- Complete ruleset
- Reference sheets (original and revised)
- Playtest notes + revision artifacts from the classroom sessions
PROJECTILE WAR — v2.0 Final (2025-11-02)
Designed and validated by Guillermo Ithier in an 11th Grade Physics classroom at Ridgefield Park Jr/Sr High School.