160 free High School trivia questions with answers — trivia quiz, new questions added Aug 2026.
These 80 trivia questions for high school students are random high school trivia in the literal sense: a question from every classroom on the timetable, shuffled together. You will meet the Pythagorean theorem and the quadratic discriminant from math, mitochondria and Mendel's peas from biology, pH and noble gases from chemistry, Newton's third law from physics, the Louisiana Purchase and the 13th Amendment from US history, the Bastille and the Berlin Wall from world history, and the books everyone was assigned, from Romeo and Juliet to The Great Gatsby and Lord of the Flies. It works two ways. Students can use it as a quick review before finals, a bell-ringer in class or a fun trivia game for a club meeting. Adults can use it to find out how much of high school actually stuck; the questions start easy and end with a few that most graduates have long since forgotten. Every answer was checked against an encyclopedia entry or primary source before publication, and each one comes with a one-line explanation that adds something you probably did not learn in class. Because every question comes straight from the high school curriculum, it also works as trivia for 15 year olds and up: a freshman or sophomore should recognise most of it, and the hard ones make a fair challenge for older teens.
30 of 160 questions with answers and explanations. Play the quiz
Q 01Whose theorem says the square of a right triangle's hypotenuse equals the sum of the squares of the other sides?
Pythagoras
Babylonian clay tablets show the relationship was known a thousand years before Pythagoras was born; he just got the naming rights.
Q 02Pi is the ratio of a circle's circumference to what?
Its diameter
That makes the circumference of any circle just over three times its width, which is why 3.14 gets you surprisingly far.
Q 03What do the interior angles of any triangle add up to?
180 degrees
On a sphere the total is more than 180, which is how surveyors first proved the Earth is curved without leaving the ground.
Q 04What is the only even prime number?
2
Every other even number is divisible by 2, so it has a factor besides itself and 1 and cannot be prime.
Q 05In the quadratic formula, the expression b² − 4ac is called what?
The discriminant
If it is below zero, the equation has no real solutions; if it equals zero, the parabola just touches the x-axis once.
Q 06The imaginary unit i is defined by which equation?
i² = −1
It lets every polynomial have a full set of roots, and it shows up in real-world electrical engineering as the letter j.
Q 07What is the highest possible score on the SAT?
1600
Two sections score 200 to 800 each; the test briefly ran to 2400 between 2005 and 2016 when a writing section was added.
Q 08Which organelle is nicknamed the 'powerhouse of the cell'?
The mitochondrion
The phrase comes from a 1957 Scientific American article, and mitochondria carry their own separate DNA, inherited only from your mother.
Q 09Adenine, cytosine and guanine are three of the four bases in DNA. What is the fourth?
Thymine
In RNA the fourth base is uracil instead, which is one of the quickest ways to tell the two molecules apart on a test.
Q 10What shape do the two strands of DNA form?
A double helix
Watson and Crick proposed the shape in 1953, using X-ray images taken in Rosalind Franklin's lab.
Q 11Gregor Mendel worked out the basic laws of heredity by breeding which plants?
Peas
He grew tens of thousands of pea plants in a monastery garden between 1856 and 1863, and his results were ignored for decades.
Q 12Robert Hooke gave cells their name in 1665 because they reminded him of what?
Rooms in a monastery
He was looking at a thin slice of cork under an early microscope and saw a grid of tiny empty boxes.
Q 13Which type of cell division produces sperm and egg cells?
Meiosis
It involves two rounds of division and ends with four cells, each carrying only one copy of every chromosome.
Q 21Avogadro's number, the number of particles in one mole, is about 6.022 times ten to what power?
23
A mole of water is only about 18 grams, which gives you a sense of how small molecules are.
Q 22Newton's third law says that for every action there is what?
An equal and opposite reaction
It is why a rocket can push itself through empty space: it throws exhaust one way and gets shoved the other.
Q 23Roughly how fast does light travel in a vacuum?
300,000 km per second
The exact figure, 299,792,458 meters per second, is now the definition of the meter rather than a measurement.
Q 14Which pigment do plants use to absorb light for photosynthesis?
Chlorophyll
It reflects green light instead of absorbing it, which is the only reason leaves look green to us.
Q 15People with which blood type are called universal donors for red blood cell transfusions?
O negative
AB positive is the mirror image: those patients can receive red cells from anyone.
Q 16Which element has atomic number 1?
Hydrogen
It is also the lightest and most abundant element, making up about three-quarters of all normal matter in the universe.
Q 17On the pH scale, what value is neutral?
7
Below 7 is acidic and above 7 is basic; each step is a tenfold change, so pH 5 is a hundred times more acidic than pH 7.
Q 18Helium, neon, argon and krypton belong to which group of elements?
Noble gases
They sit in group 18 and almost never react, which is why helium balloons are safe where the Hindenburg was not.
Q 19Which Russian chemist published the first widely accepted periodic table in 1869?
Dmitri Mendeleev
He left gaps for elements nobody had found yet and predicted their properties; gallium and germanium later filled two of them.
Q 20How many chemical elements are on the modern periodic table?
118
The first seven rows were completed by 2010; everything past uranium (92) was made in a lab.
Q 24The Ring of Fire, home to about 90 percent of the world's earthquakes, surrounds which ocean?
Pacific
It is roughly 40,000 kilometers long and holds around two-thirds of the planet's active and dormant volcanoes.
Q 25What is the capital of Australia?
Canberra
It was purpose-built as a compromise after Sydney and Melbourne both demanded the title.
Q 26Which language has the most native speakers in the world?
Mandarin
Nearly a billion people speak it from birth; only when you add people who learned it later does another language come out ahead.
Q 27In which year did the American Civil War end?
1865
Robert E. Lee surrendered to Ulysses S. Grant at Appomattox Court House on April 9 of that year.
Q 28Which amendment to the US Constitution abolished slavery?
The 13th
It was ratified in December 1865; the 14th granted citizenship and the 15th protected the right to vote regardless of race.
Q 29How many amendments make up the Bill of Rights?
10
Congress actually sent twelve to the states in 1789; the two that failed dealt with congressional pay and the size of the House.
Q 30The United States bought the Louisiana Territory in 1803 from which country?
France
The price was about fifteen million dollars, roughly eighteen dollars per square mile, and it doubled the size of the country.