Math courses

Learn to model, combine, and report measurement uncertainties using absolute and relative rules, sensitivity coefficients, covariance, and careful assumptions.

Learn to read medians, quartiles, IQRs, whiskers, and potential outliers so box plots support quick, careful comparisons.

Sit, hold, start at the top. Learn the ten written marks for 0 to 9, and why a six is not a nine.

A cup of flour is not a unit of mass. Baker's percent is how a loaf survives being scaled.

Learn how forecasts, inventory, lead times, and shared information shape supply chains and the bullwhip effect.

How does a password get hashed — mechanism, parts, and limits in plain language.

How does a debit card transaction work — mechanism, parts, and limits in plain language.

Marginal layers, not a single stamp — how progressive tax brackets really stack.

Defined benefit vs contribution, funding, and risk — pensions as multi-decade machines.

How does a bank create money — mechanism, parts, and limits in plain language.

How does inflation actually work — mechanism, parts, and limits in plain language.

How does a mortgage work — mechanism, parts, and limits in plain language.

How does encryption keep messages private — mechanism, parts, and limits in plain language.

Interest on interest: the multiplicative loop that grows balances and debts over time.

How bureaus, models, and payment history compress risk into a number lenders actually buy.

Translate contexts, choose substitution or elimination, interpret intersections, and verify exact solutions under test conditions.

Use domain, slope, transformations, quadratics, exponentials, inverses, and models to read functions.

Read axes, distributions, comparisons, uncertainty, and trends so a graph becomes evidence rather than decoration.

Read confidence levels, interval width, null values, practical importance, and model assumptions without overclaiming.

Interpret p-values through null models, tails, alpha, effect size, uncertainty, and study design.

Weigh a puppy and the scale says 3,250 grams — but the vet writes 3.25 kg. Same puppy, two ways of writing it. This course shows you how a decimal point appears when you convert units, why it slides s

Volume isn't a formula to memorise — it's just counting the little cubes that fill a box. You'll pack a box with unit cubes a row, a layer, and a stack at a time, discover why length × width × height

A measurement is a number AND a unit — and half the puzzle is the unit. Learn to move up and down the metric ladder with confidence, scale a recipe, compare litres against millilitres, and catch your

Volume is just how much space fits inside a solid — and the secret is counting cubes. See why a box packed with n unit cubes has a volume of exactly n cubic units, and where the length × width × heigh

A mile and a kilometre are just two rulers for the same road — and one simple number, 1.6, is the bridge between them. Learn to turn miles into kilometres and back in your head, master the five-is-eig

Area is the space inside a shape; perimeter is the fence around it — and because they measure different things, one can change while the other stays put. Discover the surprise that twelve squares can

A shape like a staircase or a chunky letter L looks like it should need some scary new formula to measure its space. It doesn't. Every one of these solids is just a couple of plain boxes stuck togethe

Dividing is really just sharing fairly. Learn what 'equal' means, then two easy ways to do it: deal things out one by one onto plates, or gather them into equal groups and count the groups.

Line things up in neat rows and columns and something magical happens: you can count them fast, and the total is always the same. This little course teaches five- and six-year-olds to build arrays wit

Stop counting squares one by one! Discover that the little squares inside a rectangle line up in equal rows — so you can find the area just by multiplying the two side lengths. You'll learn why area i

Kilometres, metres, centimetres, millimetres — once you see they're all built on tens, converting between them is just sliding along a ladder. You'll switch units smoothly, even with decimals like 3.5

Three questions live inside every shape: how far is it around, how much surface does it cover, and how much space does it fill? Meet perimeter, area, and volume as one big idea — counting equal units

A measurement word problem is really a little story with one number missing. This course gives you a superpower for cracking them: instead of grabbing numbers and hoping, you draw the story — on a num

An inch is about 2.5 cm and a kilogram is about 2.2 pounds. Learn the handy bridges between metric and the older English-derived units, and estimate any measurement across both.

Some shapes aren't a plain rectangle — they have a notch, a step, or an L-shaped corner. To find how far it is around one of these, you don't need a brand-new formula. You need one detective trick: re

Hours, minutes, and seconds are just different-sized rulers for the very same time. Learn the one simple ladder — multiply by 60 to go down, divide by 60 to go up — and turn 3 hours 25 minutes into 20

You already know how to find the area of a rectangle: multiply the two sides. But what about a shape that leans over, or a triangle with a slanted edge? It turns out you don't need brand-new rules at

How much space fits inside a thing? Learn to measure volume the way it actually works — by counting identical little cubes. Build a box a layer at a time, discover why length × width × height is just

Area is just how much flat space a shape covers — and you can measure it by covering the shape with little squares and counting them. Learn why rows times columns gives the answer fast, and use area m

Discover what area really measures — the unit squares that cover a shape. You'll count squares, learn the length × width shortcut, tell area apart from perimeter, and find the area of L-shapes and T-s

Kilometers to meters, hours to minutes, weeks to days — switching between units sounds tricky, but it all comes down to one friendly idea: the SAME amount can be written as a different number. Learn t

Grow a ruler in your head. Use benchmarks to estimate lengths and weights, learn the metric family from millimetres to kilometres, and settle tricky questions like whether 1.5 kg or 1,200 g is heavier

Sharpen your ruler skills to the half and quarter inch, learn a careful method for measuring to the nearest quarter, then display your measurements on a line plot that tells the whole story at a glanc

Learn to answer the two everyday measuring questions — how heavy? and how much? — with grams, kilograms, milliliters, and liters. You'll read scales and cups accurately, estimate like a pro, and solve

The movie starts at 2:15 and runs 47 minutes — so when does it end? This is the trickiest kind of time question, and there's one move that makes every one of them easy: hop to the next o'clock first,

Perimeter is the distance all the way around a shape. Learn to add up the sides, take shortcuts for rectangles and squares, hunt down a missing side, and discover that shapes with the same perimeter c

Before you ever pick up a ruler, you can make a smart guess — and this course shows you how. You'll turn your own body into a handy ruler (your pinky nail is about a centimeter!), learn the estimate-t

Learn to read an analog clock right down to the exact minute — and then use that skill to guess how long everyday things really take.

No calculator needed! Learn how British money really works — that 100 pence make a pound — then total up a shopping basket one step at a time, turn a big pile of pence into neat pounds and pence, and

Money is just counting in groups. Once you know what each coin is worth, any pile of quarters, dimes, nickels, and pennies turns into one number — and you can add it up, write it down, and make change

Become a measuring pro. You'll pick the right tool, line up the zero the right way, walk around a shape to find its perimeter, and chart what you measured. Lots of hands-on practice with rulers, meter

The same desk is 24 inches and about 61 centimeters. A number needs a unit, and the bigger the unit, the smaller the count — from inches to seconds to February.

Learn to read any clock! Meet the hour hand and the minute hand, count minutes by fives to tell time to five minutes, and figure out a.m. from p.m. by picturing a day as a circle the clock travels twi

Read any clock to the exact minute, then crack the code that connects the two ways we write time. Turn 3:45 pm into 15:45 and back again without breaking a sweat.

See what actually happens in the hours after you click buy — and why almost none of it is arranged the way you'd expect. You'll learn why modern warehouses shelve items at random on purpose, why your

A supply chain is not a pipeline run from a control room — it is a relay of custody handoffs between strangers, and it fails at the seams rather than in the middle. You'll learn why the ocean is the r

Ride along with the industry that delivers nearly everything you own its final miles. You'll understand tractor-trailers as machines, hours-of-service rules, freight brokerage, and why the loading doc

See the airline as a machine for keeping expensive aircraft in the air: hub-and-spoke networks, crew scheduling, and the cascade when weather breaks the plan. You'll understand why your flight is pric

Why is the price of moving a box across an ocean the most volatile major price in the world economy? Follow the ship rather than the box: why vessels grew to 24,000 containers, why canal locks decide

Extend calculus into three dimensions and beyond. You'll work with partial derivatives, multiple integrals, and vector fields used across physics and engineering.

Learn the equations that describe change over time. You'll solve the main types of differential equations and use them to model motion, growth, and oscillation.

Learn to prove things rigorously. You'll master direct, contradiction, and induction proofs and build the reasoning habits that make higher math possible.

Explore the deep patterns hidden in whole numbers. You'll study primes, divisibility, and modular arithmetic and see the ideas that secure modern encryption.

See what stock, bond, and other markets really do. You'll understand what is traded, how prices form, and the role of exchanges, investors, and risk without any tips.

Build a clear-eyed understanding of your own money. You'll learn budgeting, debt, saving, and compound interest as concepts, so you can reason about decisions yourself.

Understand how investment instruments actually work, not what to buy. You'll learn what stocks, bonds, and funds are, how risk and diversification behave, and what fees do.

Understand how products find their customers — and why the central act of marketing is choosing who you're NOT for. You'll learn segmentation by jobs rather than demographics, positioning, why the 4Ps

Move into inference: drawing conclusions from samples. You'll build confidence intervals, run hypothesis tests, and read regression output critically.

Learn the language of business. You'll read the three core financial statements, understand debits and credits, and follow a transaction from entry to the balance sheet.

Go deeper into how businesses measure and report: revenue recognition, depreciation, inventory, deferred tax, consolidation and goodwill — then build the cash flow statement that checks every one of t

Understand how companies raise and use money: the time value of money, why NPV is the only rule that's right, where the discount rate comes from, and what capital structure can and can't do.

Your deposit is an IOU, not a box. Lending creates that money; the same mismatch that funds a thirty-year mortgage is what makes a run possible.

Demystify the biggest loan most people take. You'll see where the payment number comes from, why early payments are almost all interest, and who bears which risk — mechanics, not advice.

Understand the business of pooling risk. You'll see how premiums, deductibles, and payouts fit together and how insurers price the chance that something goes wrong.

Understand the tax system as a system, not as advice. You'll follow how income, brackets, deductions, and withholding fit together and where public money comes from and goes.

Understand the machinery of property: you never buy land, you buy an invisible bundle of rights — and every institution in real estate exists to make that bundle certain enough to trade. Covers title,

See how new companies are actually built and funded — mechanisms, not mythology. You'll learn cap tables, dilution, preferred stock and the liquidation preference that can make a $50M exit worth nothi

Follow a product from raw material to your doorstep and find that a supply chain is an information system wearing a logistics costume. Why inventory exists, why steady demand turns to chaos upstream.

Learn negotiation as joint problem-solving rather than performance. You'll understand interests beneath positions, why your BATNA — not your nerve — is your real leverage, how differing priorities cre

See the machinery behind the ads you see all day. You'll learn how attention is targeted, auctioned in under a tenth of a second, and measured — and why one famous experiment found the same ads return

Learn from four centuries of bubbles, panics and recoveries — starting with the discovery that the most famous one, tulipmania, mostly didn't happen the way you were told. You'll trace South Sea, 1929

Explore the math behind computing and logic. You'll work with sets, proofs, graphs, and counting arguments that underpin algorithms and cryptography.

Learn to describe and reason about data honestly. You'll summarize distributions, understand probability basics, and interpret averages and spread without being fooled.

Learn the mathematics of change from the ground up. You'll understand limits, compute derivatives, and use them to find rates, slopes, maxima, and minima.

Rebuild the algebra skills most adults have let slip. You'll solve equations, work with exponents, and read and manipulate the formulas that show up everywhere.

Revisit shapes, angles, and the triangle math behind measurement. You'll compute areas and volumes and use sine, cosine, and tangent with confidence.

Bridge algebra and calculus by mastering functions. You'll graph and transform functions, handle logarithms and exponentials, and be ready for a first calculus

Learn how individuals, firms, and markets make decisions. You'll understand supply and demand, price, and why markets sometimes fail to allocate things well.

Continue into integration and its many uses. You'll evaluate integrals, compute areas and volumes, and work with infinite series and convergence.

Understand the economy as a whole. You'll follow GDP, inflation, and unemployment and see how growth, spending, and policy shape the world you live and work in.

Master the math of vectors, matrices, and linear systems that powers modern data and graphics. You'll solve systems, multiply matrices, and understand eigenvalues.

Learn to write money the proper way — using the £ and p signs and the decimal point to show pounds and pence.

Read an analog clock to the nearest five minutes by counting the minute hand around the clock in 5s.

Use a ruler the right way, measure in centimetres, learn that 100 cm make 1 metre, and compare the lengths you find.

Read length stories carefully, decide whether to add or subtract, and solve everyday problems with centimetres.

Learn how days build into weeks, weeks into months, and months into a whole year — and put them all in order.

Get to know coins, add them up to find a total, and work out the change by counting on.

Compare lengths, weights, and amounts using longer, shorter, heavier, lighter, more, and less — always using the same unit.

Compare how long everyday activities take using seconds, minutes, and hours, and put them in order from quickest to longest.

Learn to pick the best unit to measure length, weight, and amount — small units for small things, big units for big things.

Add and subtract lengths, weights, and amounts — keeping the units the same so the numbers line up.

Grab some cubes and a scale! Learn to measure how long things are by lining up cubes, and to weigh things to see what is heavier and lighter.

Great mathematicians don't just calculate — they see how numbers are built and rearrange them to make the maths easy. Learn the structure tricks the pros use.

How long? How heavy? How long does it take? Meet the friendly world of measuring — length, weight, and time — with lots of things to look at and sort.

From lemonade to maps to mixing paint, ratios show how amounts go together. Learn to read a ratio, scale it up fairly, and solve real-world problems.

Full or empty? Holds a lot or a little? Let's pour and explore how much different containers can hold — with cups, jugs, and buckets!

Tick tock! Meet the clock and its two hands, then learn to read o'clock and half past times. A warm, gentle first step into telling the time.

Crack the code of any number pattern. Learn to spot the step, build a general rule like 3n + 1, and predict any term you like.

Every word problem can be drawn, tabled, or written as an equation. Learn three powerful ways to picture a problem — and pick the one that cracks it fastest.

Which is bigger? Who has more? Let's look, point, and compare! A warm first adventure into bigger and smaller, more and fewer, taller and shorter.

Clink, clink! Meet the penny, nickel, dime, and quarter. Learn each coin's name, what it's worth, and how to count them up.

You don't have to memorize every fact — you can grow new ones from patterns you already know. Spot the rules hiding in the times tables and use one fact to unlock the next.

Real problems rarely finish in one move. Learn to spot the hidden second step, solve one piece at a time, and always answer the question that was actually asked.

Big, twisty problems are beatable with the right approach. Learn a four-step method and a toolkit of strategies — draw a picture, work backwards, list systematically — then carry a hard problem all the way to a checked answer.

Fractions, decimals, and percents are three ways of saying the very same amount. Learn to switch between them, compare them, and use them to reason about sales, scores, and real-life shares.

A good plan turns a tangled problem into simple steps — and a good check catches mistakes before they cost you. Learn to map out the steps, solve them, and prove your answer makes sense.

Big multiplications get easy when you split numbers by place value. Break a number into tens and ones, multiply each part, and add them back — the distributive property in action.

Turn everyday stories into math you can solve. Draw the situation as a bar model, write it as an equation with a symbol for the unknown, then solve and explain what the answer really means.

Every number pattern hides a rule. Learn to spot the step-by-step rule, discover the position rule that jumps straight to any term, and use it to predict numbers far down the line.

In math, an answer isn't enough — you have to prove it. Learn to back a claim with reasons, disprove a claim with a single counterexample, and judge whether a statement is always, sometimes, or never true.