Learn by doing,
not by reading.
Rooms of questions you can finish on a bus, labs where you build things that actually work, and live games for a whole class. Free to play, free to make.
A computer can compare two lists of numbers, but not two words directly. So before it can tell that "big" and "large" are alike, it has to…
A real question from Before words become arrows. Pick one — this is exactly how it feels in a room.
Rooms ask you questions. Labs hand you the parts.
Build something, test it, break it, and only move on once it works. Nothing is marked by comparing you to a reference answer — your circuit is run against every possible input, so anything that genuinely works, works.
- 1Close the circuit
- 2Which way round
- 3Pick the resistor
- 4Ohm's law
- 5Two at once
- 6Why isn't it working
- 7A switch is a gap
- 8A pin is a switch
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Before words become arrows
What Words as arrows builds on: why a computer needs words as numbers, when two arrows point the same way, subtracting one arrow from another, and analogies in plain words. About ten minutes.
Froga
Database Isolation Levels: How Concurrent Transactions Avoid Chaos
A look at what can go wrong when several transactions touch a database at the same time, and the isolation levels SQL databases use to control it. For anyone who already knows what a database table is and wants to understand what happens under concurrent load.
Froga
Nobelpriset i fysik 2026: Neutriner och IceCube
Om Nobelpriset i fysik 2026, som belönade upptäckten av neutriner från rymden med observatoriet IceCube. Passar dig som vill hänga med i veckans stora vetenskapsnyhet.
Alice
Dört modern web uygulama açığı
Modern web uygulamalarını tehdit eden gerçek açıklar. Her teknoloji kimliğini nasıl ele verir, açık tam olarak neyi mümkün kılar ve nasıl kapatılır. Express, Next.js, Django ve Apache. Küçük bayraklar saklı.
Froga
Zafiyet avına çıkmadan önce
Web güvenliğine yeni başlayanlar için kısa bir sözlük: CVE ve CVSS nedir, istek–yanıt nasıl çalışır, RCE ile kimlik doğrulama/yetkilendirme ne demek, ve sırada hangi lab ve odalar var. Yaklaşık on dakika.
Froga
Compound Interest: How Money Grows Faster Over Time
An introduction to how compound interest works and why it grows savings and loans faster than simple interest. Good for anyone curious about the maths behind saving, borrowing or investing.
Froga
Before the chance machine
What Chance machines builds on: a chance worked out by counting, why all the chances add up to 100%, and when to multiply chances and when to add them. About ten minutes.
Froga
Before the network
What Machine learning 2 builds on: the logic gates again, what makes a neuron fire, what a feature is, and why a perfect score on practice questions can mislead. About ten minutes.
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