Fractals: from simple rules to nature’s complexity
Sierpiński, Cantor, Koch, Mandelbrot and Julia explained through constructions, calculations and natural examples. A laboratory for building, measuring and exploring.
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Featured articles and games
Start with the first article, then explore online games and more selected articles.
Online games
Between the points and beyond: interpolation, regression and least squares
Lines, exponentials, powers and parabolas: identify the question, calculate coefficients and examine data in a visual laboratory.
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From logarithm to algorithm: the hidden science of anagrams
Words meet permutations and computational thinking: learn to count, check and invent anagrams without losing a single letter.
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Percentages: from meaning to the return to the original value
What % means, how to convert numbers and fractions, how increases and discounts combine, and which percentage reverses a previous change.
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Percentages of what? Groups, different bases and rate ratios
Decode percentages with different denominators: shares, rates, counts, comparisons between groups A and B, and an interactive laboratory with editable examples.
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Computational thinking: from intuition to precise algorithms
From seeing an answer to explaining a procedure: 17 digit examples, three worked applications and a method for designing, testing and reusing algorithms.
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Tower of Hanoi: rules, strategy and recursion
From the first moves to recursive strategy: examples with one, two and three disks, the minimum move count and an interactive laboratory with ten levels.
ReadFrom a fraction to a percentage
A path from ratios and equivalent fractions to the idea that a percentage is simply a fraction with denominator 100.
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Computational thinking in everyday life
Eleven everyday situations for organising activities, coordinating people and checking assumptions. With explained questions and an interactive laboratory.
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Word problems without equations: 13 arithmetic methods and 36 worked problems
A toolkit for primary school: 13 strategies, 36 word problems, concrete examples and step-by-step solutions to reveal only after trying for yourself.
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From problem to algorithm: sequences, decisions and loops
Build ordered instructions, choose with IF/ELSE and repeat with REPEAT or WHILE. Human/machine examples and the Guide the robot laboratory.
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Understand. Try. Try again.
Computer science quizzes, mathematics games, and clear explanations. Learn at your own pace by following your curiosity.
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Which data structure would you use?
Stack LIFO
FIFO queue
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5min
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Computer science
From the web to algorithms, one question at a time.
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Numbers, shapes, and strategies to put to the test right away.
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Computer basics and computer architecture
Each attempt draws 15 questions from a bank of 100 original questions about hardware, software, operating systems, files, networks, and security. This is an independent, unofficial practice activity inspired by Computer Essentials topics.
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Quizzes
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Online Essentials
Each attempt draws 15 questions from a bank of 100 original questions about Web browsing, online search, communication, email, and calendars. This is an independent, unofficial practice activity inspired by Online Essentials topics.
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Games
Intermediate
The hidden sequence
Observe the pattern, form a hypothesis and find the next number.
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Can you make 24 using 3, 3, 7, and 7?
Use each number only once and combine the four basic arithmetic operations.
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