★ Number Line Leap
playablenumber_line_leap · math · mapper.number_line
Concept: Magnitude, fractions, negatives
Player does: Land on 3/8 or −2.5 with only coarse landmarks labeled
Breaks: A bigger denominator means a bigger fraction
A fraction's size comes from how far along the line it lands, and a bigger denominator makes each step smaller.
Equivalent Landing
playableequivalent_landing · math · mapper.number_line
Concept: Equivalent fractions
Player does: Two different-looking fractions must land on the same stone
Breaks: Different numerals mean different amounts
Equivalent fractions name the same point on the line, no matter how they are written.
Log Scope
playablelog_scope · math · mapper.number_line
Concept: Scientific notation, orders of magnitude
Player does: Place 10⁻⁹ m, 10³ m, 10⁶ m on a zoomable log line
Breaks: 10⁻⁹ is a large negative number
A negative exponent means a tiny positive number; each step on a log line multiplies by ten.
Integer Lift
playableinteger_lift · math · mapper.number_line
Concept: Signed-number arithmetic
Player does: Ride the elevator through basement floors: −3 − (−5)
Breaks: Subtracting a negative makes a number smaller
Subtracting a negative moves you up the line, because it undoes a move down.
Intersection Hunt
playableintersection_hunt · math · mapper.plane
Concept: Systems of equations
Player does: Mark the one point both laser paths pass through
Breaks: A solution only has to satisfy one equation
A system's solution must satisfy every equation at once, which is exactly where the lines intersect.
Allowed Region
playableallowed_region · math · mapper.plane
Concept: Inequalities
Player does: Only tiles where y < 2x + 1 are solid; mark the safe region
Breaks: Multiplying by a negative keeps the inequality direction
Multiplying or dividing an inequality by a negative number flips the inequality's direction.
Distance Field
playabledistance_field · math · mapper.number_line
Concept: Absolute value
Player does: Beacons light where |x − 3| < 2; mark the whole lit stretch
Breaks: |x| just deletes a minus sign, so |x| = x
Absolute value is distance from zero, so |x| equals x only when x is nonnegative; otherwise it flips the sign.
Coordinate Treasure
playablecoordinate_treasure · math · mapper.plane
Concept: Distance & midpoint
Player does: Mark the midpoint between two torches on the grid
Breaks: The midpoint is the difference of the coordinates
The midpoint is the average of the two points' coordinates, not their difference.
Circular Navigator
playablecircular_navigator · math · mapper.plane
Concept: Unit circle
Player does: Walk the unit circle to where the x-shadow reads the given cos θ
Breaks: sin θ is the x-coordinate
On the unit circle cos θ is the x-coordinate and sin θ is the y-coordinate.
Projection Machine
playableprojection_machine · math · mapper.number_line
Concept: sin & cos as projections
Player does: Predict where the rotating point's shadow lands at θ
Breaks: sin and cos are unrelated functions
Sine and cosine are the two shadows of one rotating point, which is why they share a period and trade peaks.
Radian Rune Line
playableradian_rune_line · math · mapper.number_line
Concept: Radian measure
Player does: Step onto 5π/6 on the unrolled circle
Breaks: π radians is a full turn
A full turn is 2π radians because the unit circle's circumference is 2π; π is half a turn.
Vector Winds
playablevector_winds · math · mapper.plane
Concept: Vector addition
Player does: Place fans; mark where their combined push carries you
Breaks: Vectors add like numbers (3 + 4 = 7)
Vectors add component-wise (or tip-to-tail), so their combined magnitude generally is not the simple sum of their lengths.
Component Split
playablecomponent_split · math · mapper.plane
Concept: Components
Player does: Split thrust into x and y engines that land you on target
Breaks: Components add up to the magnitude
A vector's magnitude comes from the Pythagorean combination of its components, not their simple sum.
Scatter Landscape
playablescatter_landscape · math · mapper.number_line
Concept: Correlation
Player does: Place each scatter plot's r on the −1…1 line
Breaks: r = 0 means no relationship of any kind
A correlation of r = 0 rules out a linear relationship but not a strong nonlinear one.
Evidence Updater
playableevidence_updater · math · mapper.number_line
Concept: Bayes' theorem
Player does: After the test result, set the belief meter
Breaks: A 99%-accurate test means a 99% chance you're sick
Bayes' theorem shows the chance of being sick given a positive test also depends on the disease's rarity, which can make it far below the test's accuracy rate.
Restricted World
playablerestricted_world · math · mapper.number_line
Concept: Conditional probability
Player does: Irrelevant outcomes vanish once the condition is known; place P(A|B)
Breaks: P(A|B) = P(B|A)
Conditional probability is not symmetric in general: P(A|B) and P(B|A) can be very different values.
Z-Score Rapids
playablez_score_rapids · math · mapper.number_line
Concept: z-scores, normal distribution
Player does: Place the raft at the reading's z-score
Breaks: z = 2 means twice the average
A z-score of 2 means the value is two standard deviations above the mean, not double the mean itself.