Learn how markets work.Then find out if you'dhave been right.
8 short lessons teach you what a P/E ratio is, how to read a chart, and what makes a company hard to compete with. Then 5 challenges drop you into real moments in market history — 2003, 2008, 2011 — with only the information investors had at the time.
8 lessons · 5 challenges · free · no account needed
Try both right now.
No account. No scrolling. Pick one.
A lesson checkpoint
From: Financial Ratios
P/E ratio compares a company's stock price to its:
A challenge decision
1 / 3
Apple Inc. · January 15, 2008
Share price
$169.04
Revenue (FY2007)
$24.0B, +24%
P/E ratio
43×
The iPhone is six months old and under 1% of sales. Revenue grew 24% and the company has $15.4B in cash and no debt — but at 43× earnings, into a weakening economy.
What do you do until January 20, 2009?
The lesson on the left is what the 43× on the right means. That link is the whole idea.
Start with the vocabulary.
8 lessons, four to eight minutes each. Read a section, answer a quick checkpoint, keep going. 25 real charts and 48 questions, every one connecting back to a decision you'll have to make later.
Start Here
What analysing a company actually involves, and how to work through the rest.
1 lesson · 5 minutes · 4 checkpoint questions
Investing Foundations
The vocabulary the challenges assume — statements, ratios and what makes an advantage durable.
3 lessons · 12 minutes · 17 checkpoint questions
Chart & Trading Fundamentals
Trading styles set your timeframe, chart anatomy gives you the vocabulary, patterns build on it, and risk decides whether any of it helps.
4 lessons · 28 minutes · 27 checkpoint questions
One of 25 charts across the lessons.
Every diagram is drawn for the point it is making. This one is from Anatomy of a Stock Chart, where four numbers — open, high, low and close — become one mark on a page.
Browse all 8 lessons →Learn it, then prove it.
Learn the vocabulary
Short lessons with real charts. Read a section, answer a checkpoint, move on. You'll know what a P/E ratio is, how to read a candlestick, and what makes a business hard to compete with.
Stand at a real date
A real company on a real day — January 2008, September 2011. You get the actual financials and the actual price, and nothing that happened afterwards. The chart stops where you're standing.
Make the call, then find out
In or out — buy it, or stay in cash. Lock it in; you can't change it, which is the point. Then the chart completes and you learn whether your reasoning held up.
5 moments worth arguing about.
Each one runs through five decisions and a decade or more of history.
AAPL
Apple Inc.
“It's an iPod company with an expensive side project.”
Jan 2008 → Jul 2026
AMZN
Amazon.com, Inc.
Never had a profitable year, owes more than it owns.
Jan 2003 → Jul 2026
NFLX
Netflix, Inc.
Just raised prices and customers are furious.
Sep 2011 → Jul 2026
TSLA
Tesla, Inc.
One car, huge losses, about to post a first profit.
May 2013 → Jul 2026
NVDA
NVIDIA Corporation
Down 48% from its peak after the crypto bust.
Jan 2019 → Jul 2026
Fake money teaches you nothing.
Paper-trading apps let you buy imaginary shares and wait. You learn what the market did — not whether your reasoning was any good. Here, the answer already exists. You commit, and then you find out, in seconds, whether you were right and why.
Try it yourselfStock simulators
What you trade
Imaginary future
Feedback
Weeks or months
Right answer
Doesn't exist yet
What you learn
What the market did
Marketpast
What you trade
Real market history
Feedback
Immediately
Right answer
Already happened
What you learn
Whether your reasoning held up
Most people get these wrong.
54%
how far Apple fell in the twelve months after the January 2008 challenge begins — while the business kept growing.
73%
how much Netflix lost in three months after raising prices in September 2011, having looked unstoppable all year.
55×
what NVIDIA returned by 2026, from a January 2019 chart that looked broken after the crypto bust.
You already have an opinion. Go test it.
8 lessons and 5 challenges. Free. No account needed.
48
Checkpoints you can't skip past
5
Challenges, five decisions each
25
Charts drawn for the point they make
Tell me what's missing
This is in beta and still changing. If something confused you, or there's a company you'd want to stand in front of that isn't here yet, that's the most useful thing you can say.
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