How to Prove a Number Trick Always Works
Learn to simplify by collecting like terms, open brackets without losing a sign, test whether two expressions are equivalent, and use algebra to explain why a trick never fails.
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The Rule Hiding Inside a Growing Matchstick Pattern
Learn to turn situations into expressions, name the terms and coefficients, substitute values, and find the general rule behind any pattern that grows step by step.
Read articleHow to Find a Number Between 3.4 and 3.5
Learn to place decimals on a number line, compare them by place value rather than digit count, convert between units, and add and subtract without misaligning the point.
Read articleWhat Lives in the Space Between 4 and 5
Learn why we need pieces smaller than one, what each digit after the point is worth, how to switch between fractions and decimals, and how to write money and lengths.
Read articleCompare Two Sums Without Working Either of Them Out
Learn to build an expression from a situation, rearrange terms safely to make arithmetic easy, compare expressions by reasoning, and open brackets without losing a sign.
Read articleIs That Number Even Possible? A Quick Sanity Check
Learn to read numbers up to crores, write them in different forms, round to any place, and judge in seconds whether a huge number in a news report is believable.
Read articleThe Moon Never Turns Its Back on Us
Learn why the Moon shines without making light, what the phases really show, how solar and lunar eclipses differ, and why one is far easier to see than the other.
Read articleSeasons Have Nothing to Do With Being Closer to the Sun
Learn how rotation makes day and night, how revolution and a tilted axis make the seasons, and why summer in India is winter in Australia.
Read articleWhy AMBULANCE Is Written Backwards on the Van
Learn how a pinhole camera flips an image, what reflection does to light, the four rules for a plane mirror image, and how periscopes and kaleidoscopes work.
Read articleWhy You Can't See Around a Corner
Learn which objects make their own light, how materials differ in what they let through, the experiment proving light travels straight, and what controls a shadow's size.
Read articleHow Water Climbs to the Top of a Tall Tree
Learn how roots draw water up through the xylem, how the phloem carries food down, what transpiration does for a plant, and why plants breathe day and night.
Read articleHow a Leaf Builds Food Out of Air and Sunlight
Learn the four things photosynthesis needs, what stomata actually do, how the iodine test proves a leaf made starch, and why plants are called producers.
Read articleWhat Your Pulse Is Actually Telling You
Learn what blood is made of, how arteries and veins differ, why your pulse matches your heartbeat, and how the kidneys clean the blood every single day.
Read articleBreathing and Respiration Are Not the Same Thing
Learn why breathing is only half the story, how the ribs and diaphragm move air in and out, and why an earthworm needs to stay damp to stay alive.
Read articleThe Journey Food Takes Through Your Body
Learn the different ways animals take in food, the parts of the human digestive system, the five steps of nutrition, and how a cow's digestion differs from yours.
Read articleWhat the Shape of a Line Tells You About a Journey
Learn to tell uniform motion from non-uniform, calculate speed in m/s and km/h, find average speed, and read a distance-time graph at a glance.
Read articleA Heavier Pendulum Bob Does Not Swing Any Slower
Learn how time was measured before clocks, what a pendulum's time period means, why only its length matters, and how to convert confidently between time units.
Read articleWhy the Sea Breeze Reverses After Dark
Learn why land and water heat at different rates, how the Sun drives the whole water cycle, where rain goes after it lands, and how an ice stupa stores winter water.
Read articleWhy a Metal Spoon Burns Your Hand but a Wooden One Doesn't
Learn the one direction heat always travels, the three ways it moves, and why light clothes in summer and woollen clothes in winter both make scientific sense.
Read articleWhat a Growing Body Actually Needs
Learn how to build a balanced diet for a growth spurt, the hygiene that matters during adolescence, healthy ways to handle mood swings, and how to stay safe online.
Read articleEveryone Grows Up on Their Own Timetable
Learn what adolescence and puberty mean, the physical changes hormones bring about, and the facts about the menstrual cycle that clear up common myths.
Read articleThree Things a Fire Needs, and What Happens If You Remove One
Learn the word equation for rusting, four ways to stop it, the three conditions combustion needs, and how weathering slowly turns rock into soil.
Read articleOne Burning Candle Shows Two Kinds of Change at Once
Learn the one test that separates physical from chemical change, the five signs a new substance has formed, and why a candle demonstrates both at the same moment.
Read articleWhy Sodium Is Kept Under Oil
Learn what happens when metals burn, react with water and react with acids, how to test for hydrogen, and why iron rusts while stainless steel does not.
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