Facts for Ages 11–13
1607 facts perfect for this age group
Fresh olives straight from the tree are so bitter they are almost inedible. They contain a compound called oleuropein that must be removed by curing in brine, salt, or lye for weeks or months before they can be eaten.
Genghis Khan built the largest contiguous land empire in history, stretching from the Pacific Ocean to Eastern Europe by the time of his death in 1227 — covering about 24 million square kilometres.
Your stomach acid is so strong (with a pH as low as 1.0) that it could dissolve a metal razor blade. The stomach lining replaces itself every three to four days to survive.
The 1815 eruption of Mount Tambora caused 'The Year Without a Summer' in 1816 — it snowed in June in North America!
Electric eels can generate shocks of up to 600 volts — enough to stun a horse — using special cells in their bodies that act like tiny batteries.
In the 17th century, nutmeg was so valuable it was worth more than its weight in gold. European nations fought wars and colonised islands just to control the nutmeg trade.
The Berlin Wall, which divided communist East Germany from West Germany for 28 years, fell on November 9, 1989, partly because of a government spokesman's mistake. At a press conference he misread his notes and announced that border crossings were open immediately. Crowds rushed to the checkpoints and guards, overwhelmed, let them through.
The ocean contains about 20 million tons of dissolved gold, but it is too spread out to collect.
Cricket has been played since at least the 16th century. The earliest definite reference dates to 1598 in a court case in England.
Sea turtles can sense Earth's magnetic field and use it like a built-in GPS to navigate thousands of miles.
A giant Pacific octopus has one central brain and eight smaller brains — one in each arm — giving it a total of nine.
Babies can hear and distinguish every sound in every language until about 10 months old, then they start specialising.
The first general-purpose computer, ENIAC, filled an entire room and weighed over 27 tons.
Old English, spoken in England from about 450 to 1100 CE, looks completely foreign to modern English speakers. Even a familiar text like the Lord's Prayer would be almost unrecognisable in its Old English form.
The term 'lingua franca' (meaning a shared language used between speakers of different native languages) originally referred to a specific pidgin language based on Italian used by traders throughout the Mediterranean from the 11th to 19th centuries. Today English often serves as a global lingua franca. The term itself has become a common English phrase.
Whale sharks can live for over 130 years, making them one of the longest-lived fish. Scientists estimate their age by counting growth rings in their vertebrae, similar to counting tree rings.
Translating ancient texts is an ongoing intellectual challenge that often requires expertise in linguistics, history, and culture. Many ancient words have uncertain meanings, and context can change dramatically across 3,000 years. The Rosetta Stone breakthrough was possible only because the same text appeared in three scripts, allowing cross-referencing. Without such bilingual texts, many ancient scripts would still be undeciphered.
Before the development of surgical anesthesia in the 1840s, surgery was performed on fully conscious patients, who had to be held down while screaming in agony. The first public demonstration of ether anesthesia was performed by dentist William Morton in Boston in 1846. Surgeons who had previously worked as fast as possible to minimize patient suffering could now take the time to perform more complex and careful operations.
Volcanic islands often develop unique species found nowhere else on Earth because their isolation means plants and animals evolve independently over millions of years. The Galápagos Islands, formed by volcanic activity, are famous for the unique wildlife that inspired Charles Darwin's theory of evolution.
Some scientists believe Diplodocus could crack its tail like a whip, potentially creating a supersonic boom louder than a gunshot. The tip of the tail may have exceeded the speed of sound.