A self-paced learning notebook
Learn how the world actually works.
Rollo & Freya's learning project. We want to teach kids how the world works from a practical point of view — led by their curiosity, and delivered hands-on, one topic at a time.
Start with the foundations
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Foundations What is Science?
How science actually works — observation, hypotheses, and what makes a question testable.
10 min beginner
Foundations How Big Is a Billion, Really?
Everyone knows a billion is bigger than a million. Almost nobody feels HOW much bigger. It's a thousand times — which means a million is practically sitting on zero. Here's how to make that gap something you can feel.
12 min beginner
Chemistry Atoms: The Building Blocks
What atoms are made of, how to read an element, and the difference between atomic number and mass number.
14 min beginner