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WillTeachMaths

Thinking-first maths tools

Game theory and decisions

Voting systems reveal that fairness is mathematical, not automatic.

This prototype explores a deceptively simple question: if the same people vote under different rules, do we always get the same winner?

Use it as a neutral mathematical lab for plurality, ranked choices, runoff voting, Borda scores and head-to-head fairness checks. The aim is not to tell students what to think politically, but to show that rules shape outcomes.

Voter profile

Change the electorate, then predict who wins.

Each row is a group of voters with the same ranked preferences. The candidates are deliberately neutral: imagine a school is choosing which shared space to improve.

Total voters: 76

Before looking at the result cards, choose a rule and predict whether it rewards first choices, broad support or majority support.

Library

24 first-choice votes, 32%

Park

26 first-choice votes, 34%

Sports Hall

26 first-choice votes, 34%

Plurality

Park

Only first choices count. This is simple, but it can ignore second-choice support.

Park26
Sports Hall26
Library24

Borda count

Library

Rankings earn points: 2 for first, 1 for second, 0 for third. This often rewards compromise candidates.

Library96
Park68
Sports Hall64

Instant runoff

Park

The lowest first-choice candidate is eliminated, then those ballots transfer to their next active choice.

Park42
Sports Hall34
Library0

Pairwise fairness check

Does anyone beat every other candidate head-to-head?

Condorcet winner: Library

Library vs Park

50 prefer Library; 26 prefer Park.

Head-to-head winner: Library

Library vs Sports Hall

46 prefer Library; 30 prefer Sports Hall.

Head-to-head winner: Library

Park vs Sports Hall

42 prefer Park; 34 prefer Sports Hall.

Head-to-head winner: Park

Majority

No candidate has more than half of first choices, so the idea of a fair winner is less obvious.

Rule sensitivity

Different voting rules currently choose different winners. That is the mathematical discomfort worth discussing.

Runoff story

Round 1: Library is eliminated. Round 2: Park wins.

Joy in the process

The point is not just to finish. It is to notice, test and return.

These tools are invitations to explore. A good mistake, a surprising pattern or a question you cannot yet answer is part of the work, not a failure of it.

The challenge is deliberate: the site should support thinking, not remove the need for it.

Before changing a setting, pause and predict what you think will happen.
Change one thing at a time. What stayed the same, and what changed?
Try to create a surprising case, a broken case, or a beautiful pattern.
Ask what this connects to outside the page: maps, movement, nature, systems or decisions.
Reset, then try again with a new question in mind.

Guided exploration

Use the prototype to create predictions, not just observations.

Before changing the sliders, predict which voting rule will choose each winner.
Find a voter profile where plurality and instant runoff choose different winners.
Try to make the Condorcet winner lose under plurality. What feels unfair about that?
Look for a compromise candidate: not the most first choices, but rarely ranked last.

Future extensions

This can become a wider social choice and fairness strand.

Add approval voting and score voting for comparison.
Add a spoiler-candidate mode where a new similar option enters the election.
Add Arrow's impossibility theorem as a guided, visual discussion.
Add classroom election templates for anonymous preference collection.