9th Grade Trivia
0Loading crowd target
0Loading crowd target
8correct to beat the crowd
158 free 9th Grade trivia questions with answers — trivia quiz, new questions added Aug 2026.
This 9th grade trivia quiz is built around what a typical freshman actually studies: Algebra I (slope, linear and quadratic equations, primes, the Pythagorean theorem), Biology (cells, photosynthesis, mitosis, DNA, Mendel and Darwin, food chains), World History (Mesopotamia and Egypt through Greece, Rome, the Renaissance, the French Revolution, the Industrial Revolution and World War I) and English (Romeo and Juliet, To Kill a Mockingbird, Of Mice and Men, The Odyssey, Lord of the Flies, Animal Farm and The Great Gatsby). If you want the wider school experience rather than the syllabus, our high school trivia quiz covers that. The easy questions are the ones any 14-year-old should get: what a prime number is, which family Juliet belongs to, who wrote On the Origin of Species. From there it climbs to the things that separate an A from a B: the year Mendel published, why the Bastille held only seven prisoners, what the discriminant tells you, which emperor moved the capital to Byzantium. Teachers can use it as a review game; parents can use it to check whether they still remember freshman year. Every answer was checked against the encyclopaedia entry for the topic before publishing, and the sentence that supports it is stored with each question.
30 of 158 questions with answers and explanations. Play the quiz
Q 01What do we call a natural number greater than 1 that is not a product of two smaller numbers?
Prime
The primes are the building blocks of every whole number, which is why 1 is left out of the club.
Q 02Slope is defined as the ratio of which two things?
Rise to run
Slope is rise over run: the change in y divided by the change in x between two points on the line, so a horizontal line has slope zero.
Q 03What is the maximum number of solutions a quadratic equation can have?
Two
The graph is a parabola, and a parabola can cross the x-axis at most twice.
Q 04In ax² + bx + c = 0, what is the name given to c?
Constant coefficient
c is the constant coefficient, or constant term: a is the quadratic coefficient and b the linear coefficient, and if a were zero the equation would just be linear.
Q 05Which method is used to derive the quadratic formula?
Completing the square
Completing the square: you rewrite ax² + bx + c = 0 so the left side is a perfect square equal to a constant, then take the square root and solve for x.
Q 06The Pythagorean theorem relates the three sides of which kind of triangle?
Right
The Pythagorean theorem holds only in a right triangle: the square of the side opposite the right angle equals the sum of the squares of the other two sides.
Q 07What is the name for the side of a right triangle opposite the right angle?
Hypotenuse
The hypotenuse is the side opposite the right angle and always the longest side, which is why c² = a² + b² in the Pythagorean theorem.
Q 08Around what year was Pythagoras born?
570 BC
Pythagoras was born around 570 BC on the Greek island of Samos and later founded his school at Croton in southern Italy.
Q 09Which civilisation used the Pythagorean rule over a thousand years before Pythagoras?
Babylonians
The Babylonians knew the rule by about 1800 BC: the clay tablet Plimpton 322 lists Pythagorean triples more than a thousand years before Pythagoras was born.
Q 10The word 'algebra' comes from which language?
Arabic
It comes from the Arabic al-jabr, 'the reunion of broken parts', which originally referred to setting broken bones before it meant balancing equations.
Q 11Which 9th-century Persian mathematician gave algebra its name?
Al-Khwarizmi
Al-Khwarizmi's treatise on al-jabr wa'l-muqabala, written in Baghdad around 820, gave algebra its name; his own name, Latinised, became the word algorithm.
Q 12Which 3rd-century Greek wrote the Arithmetica, an early treatment of solving equations?
Diophantus
His name survives in Diophantine equations, where only whole-number solutions count.
Q 13Who proved around 300 BC that there are infinitely many primes?
Euclid
Euclid's Elements (Book IX, Proposition 20) shows no finite list of primes is complete: multiply them all together, add 1, and the result has a prime factor missing from the list.
Q 21Bacteria and archaea belong to which broad group of single-celled organisms?
Prokaryotes
Bacteria and archaea are prokaryotes: cells with no nucleus, whose DNA sits in a region called the nucleoid rather than inside a membrane.
Q 22What is the largest membrane-bound organelle in a eukaryotic cell?
Nucleus
It holds the cell's chromosomes inside a double membrane called the nuclear envelope.
Q 23What gas do plants release as a by-product of photosynthesis?
Oxygen
The oxygen comes from splitting water molecules in the light-dependent reactions, not from the carbon dioxide the plant takes in.
Q 14What is the only even prime number?
2
Every other even number is divisible by 2, so every other prime is odd.
Q 15Which ancient Greek devised the 'sieve' used to list prime numbers?
Eratosthenes
The sieve of Eratosthenes, devised in the 3rd century BC, lists primes by writing out the numbers and crossing off every multiple of each prime you find.
Q 16The solutions of a linear equation in two variables form what shape on a graph?
A straight line
Every line in the plane can be written as ax + by + c = 0 and vice versa.
Q 17Which form of algebra, taught in schools, uses variables to stand for unspecified values?
Elementary
Elementary algebra, the kind taught in schools, introduces variables such as x to stand for unknown or unspecified values; abstract algebra, with its groups, rings and fields, comes much later.
Q 18What is the basic structural and functional unit of all living things?
The cell
The cell is the basic unit of life: every organism is built from one or more cells, and the name comes from the Latin cellula, a small room.
Q 19Who discovered cells in 1665, naming them after rooms in a monastery?
Robert Hooke
Robert Hooke coined the term in Micrographia (1665) after seeing the honeycomb of tiny compartments in a slice of cork, which reminded him of monks' cells.
Q 20Which organelles provide energy for cell functions?
Mitochondria
Mitochondria are the cell's powerhouses, where cellular respiration breaks down glucose to release usable energy; plant cells have mitochondria as well as chloroplasts.
Q 24Which plant pigment absorbs red and blue light and reflects green?
Chlorophyll
Chlorophyll absorbs red and blue wavelengths to power photosynthesis and reflects green, which is why leaves look green.
Q 25What is the name of the light-independent reactions that build sugars in plants?
Calvin cycle
The Calvin cycle uses the energy carriers made in the light-dependent stage to fix carbon dioxide into three-carbon sugars, which the plant then builds into glucose.
Q 26In which part of the chloroplast do the light-dependent reactions of photosynthesis occur?
Thylakoid membranes
The light-dependent reactions run in the thylakoid membranes, stacked into grana, where chlorophyll captures light and water is split to release oxygen.
Q 27What molecule stores the chemical energy produced by cellular respiration?
ATP
ATP, adenosine triphosphate, stores the energy released by respiration in its phosphate bonds; breaking off the third phosphate powers most of the work a cell does.
Q 28Which first stage of cellular respiration takes place in the cytosol of every living cell?
Glycolysis
Glycolysis, literally 'sugar splitting', breaks one glucose into two pyruvate molecules in the cytosol and works with or without oxygen.
Q 29How many ATP molecules per glucose do biology textbooks often say respiration makes?
38
The textbook maximum is 38 ATP per glucose: 2 from glycolysis, 2 from the Krebs cycle and 34 from the electron transport chain; leaky membranes and transport costs make the real yield nearer 30.
Q 30Cell division by mitosis produces how many daughter cells from one parent cell?
Two
Both get an identical set of chromosomes; meiosis is the one that makes four.