How lessons work

Every lesson explains the idea in plain language, works through an example with numbers, and then shows what can go wrong. Here is part of a real lesson from Part 5, Building a Portfolio. Change the numbers and see what happens.

Part 5 · Sizing and Building Positions · Lesson 2

Scaling Into a Position

Why this matters

Buying everything at once ties your whole position to a single price on a single day. Scaling in means building the position in several smaller purchases instead.

The example

You want 300 shares of STU Corp, a fictional company trading at $50. You buy 100 shares now and place orders for 100 more at $48 and another 100 at $46.

If the price falls, your average cost ends up lower than $50. If it rises, some of those orders may never fill.

How every Hyperion Entities lesson is built:

Explain the concept in plain language
Work through an example with numbers
Show why someone might use it
Show the risks and tradeoffs

Try it: STU Corp

Planned purchases
Order	Shares	Limit price	Status
1			Filled
2			Filled
3			Filled

Shares owned: 300
Total invested: $14,400.00
Average cost: $48.00

What's in a lesson

Most lessons follow this order. A short lesson skips the sections it doesn't need.

Why this matters: Where you'll run into the idea as an investor, and why it's worth your time.
What you'll learn: Two or three things you should be able to explain afterwards.
The concept: The idea in everyday language first, then the proper financial term.
Worked example: Real numbers, usually from a fictional company, so the idea can't stay abstract.
Benefits and tradeoffs: Why someone might use it, and what it costs them. Very few investing decisions have only advantages.
Common mistakes: Where people usually go wrong with the idea.
Key takeaways: A short recap you can come back to.
Check your understanding: A question or two that tests reasoning rather than memory.
What's next: How the lesson connects to the one after it.

Definitions in place

Try the underlined terms.

Financial terms are defined where they appear, so you don't have to leave the lesson to look them up. For example: if you place a at $48 and the stock never falls that far, the order doesn't fill, and your stays where it was.

Every term is also in the glossary, linked to the lessons that use it.

Questions that test reasoning

From Part 4, Valuation Fundamentals.

Company A trades at 12 times earnings. Company B trades at 30 times earnings. Can you conclude that Company A is the better investment based only on this?

Show the answer

No. A lower price-to-earnings ratio can mean a company is cheap, or that investors expect its earnings to shrink. A higher one can mean it's expensive, or that its earnings are expected to grow quickly. You'd need to know about each company's growth, risks, and quality before drawing a conclusion. A low number on its own doesn't tell you the investment is better.

Interactive tools, only where they help

Most ideas are clearest as a worked example. A few are easier to understand when you can change the inputs yourself.

Growth charts: Part 1: see how saving, investing, inflation, and fees play out over the years, with the numbers in a table beside each chart.
Financial statement explorer: Part 3: record a company's transactions and watch each one move through all three financial statements.
DCF sandbox: Part 4: change cash flow, growth, long-run growth, and the discount rate, and see how far the estimated value moves.
Capstone projects: At the end of a part: sorting, matching, and calculation tasks with a running score and a model answer.
Allocation explorer: Part 5: run any mix of stocks, bonds, and cash through real US returns from 1928 to 2025, and see its growth, worst year, and losing years.
Scaling-in simulator: Part 5: the tool above.
Entry-method comparison: Part 5: a lump sum, dollar-cost averaging, and scaling in, side by side on four different price paths.

See every lesson in the curriculum.

View the curriculum