Akademi Tukuk-OS

Fifty short lessons on how the world actually works — sky and space, weather, the planet, air, the body, life, numbers, computers, everyday machines and clear thinking. Each lesson is three plain-language paragraphs, three takeaways and one quiz question; the whole academy reads in about 6 hours spread over a month. Free, no account, no paywall. For coding paths see the Zero-to-Hero Academy; for daily facts and quizzes the Knowledge Complex.

The syllabus — ten tracks, fifty lessons

Figures in the lessons are labelled “about” or “roughly” wherever sources differ — the academy prefers an honest approximation to a false decimal.