Quick answer: Primary 2 Mathematics vocabulary helps children read and solve problems involving numbers up to 1,000, multiplication tables, equal sharing, fractions, dollars and cents, time to the minute, measurements, 3D shapes and scaled picture graphs. This page gives 200 clearly explained words and expressions, then shows what the important ones mean inside actual P2 word problems.
Under Singapore’s 2021 MOE Primary Mathematics syllabus, updated October 2025, Primary 2 introduces hundreds in place value; multiplication tables of 2, 3, 4, 5 and 10; unit and like fractions; money in decimal notation; metres, kilograms, grams and litres; telling time to the minute; common 3D solids; and picture graphs with scales. The glossary includes syllabus language and helpful classroom or everyday words. It is not an official 200-word MOE examination requirement.
In this guide:
- The full 200-word glossary, numbered and grouped
- Six Primary 2 worked word problems
- Misunderstandings to diagnose before more practice
- A four-week vocabulary and maths plan
- FAQs and links to official learning outcomes
200 useful Primary 2 Mathematics vocabulary words
These are short explanations, not dictionary exercises. For each term, point to a model, have the child say a complete example, and return to it later in a new problem. Mathematical phrases count as entries because real questions are written in phrases rather than isolated labels.
1. Numbers to 1,000 and place-value descriptions — words 1–20
- hundred — One group containing one hundred units.
- hundreds place — The position showing how many complete hundreds a number contains.
- three-digit number — A whole number from 100 to 999.
- thousand — A collection of ten hundreds; 1,000.
- place-value chart — A table that separates hundreds, tens and ones.
- expanded form — A number written as the sum of its place values, such as 400 + 30 + 6.
- standard form — The usual compact numeral, such as 436.
- digit value — What a digit is worth in its current position.
- face value — The digit itself, independent of where it appears.
- leading digit — The first non-zero digit when reading a whole number.
- trailing zero — A zero appearing after the last non-zero digit.
- rename a number — Show the same quantity in a different place-value grouping.
- exchange a hundred — Replace one hundred by ten tens without changing the total.
- exchange a ten — Replace one ten by ten ones.
- hundred-block — A model representing one hundred units.
- ten-rod — A model representing ten units.
- unit cube — A small block representing one unit.
- count by hundreds — Increase or decrease in steps of one hundred.
- skip count — Count in repeated equal jumps, not by individual ones.
- digit arrangement — The order of digits that determines a number’s value.
2. Addition, subtraction and mental computation — words 21–40
- column addition — Write digits in the correct places before adding vertically.
- column subtraction — Align place values before subtracting vertically.
- three-digit sum — An addition calculation using numbers with up to three digits.
- regrouping — Exchanging place-value units during a calculation while preserving total value.
- carry a ten — Make ten ones into one ten in an addition algorithm.
- borrow a ten — Rename one ten as ten ones in a subtraction algorithm.
- carry a hundred — Exchange ten tens for one hundred when adding.
- subtract across zero — Rename places carefully when a column has zero available ones.
- vertical working — Steps written in aligned columns instead of across one line.
- horizontal working — A calculation written across a single line.
- mental computation — Calculate using number knowledge rather than writing every step.
- adjustment — Change a number temporarily and then correct for the change.
- compensation — Balance a convenient change so the original answer stays correct.
- round-number strategy — Use an easier nearby number to calculate efficiently.
- number fact — A known relationship such as 7 + 5 = 12.
- related facts — Addition and subtraction statements built from the same numbers.
- fact family — A small collection of related operation sentences.
- inverse operation — An operation that reverses another, such as subtraction reversing addition.
- verify by addition — Use adding back to confirm a subtraction result.
- estimate a sensible answer — Predict an approximate size before checking exact working.
3. Multiplication tables and division facts — words 41–60
- two-times table — Products formed by multiplying whole numbers by two.
- three-times table — Products formed by multiplying whole numbers by three.
- four-times table — Products formed by multiplying whole numbers by four.
- five-times table — Products formed by multiplying whole numbers by five.
- ten-times table — Products formed by multiplying whole numbers by ten.
- multiplication fact — A known statement such as 4 × 5 = 20.
- division fact — A known statement such as 20 ÷ 5 = 4.
- product — The answer to a multiplication calculation.
- quotient — The answer to a division calculation.
- division sign — The symbol ÷ in a division sentence.
- equal jumps — Repeated steps of the same size on a number line.
- multiplication row — A displayed sequence of products for one times table.
- commutative multiplication — Switch the order of factors without changing the product.
- matching division — A division fact linked to a multiplication fact.
- grouping division — Divide by finding how many equal groups can be made.
- sharing division — Divide by finding how many items each recipient receives.
- two each — A situation where every person or group gets two items.
- five in each packet — A group-size statement useful for multiplication or division.
- number of packets — The count of groups to determine from given items.
- leftover after sharing — Objects not yet allocated; explain before applying further division.
4. Fractions of a whole — words 61–80
- fraction — A number representing equal parts of a whole.
- numerator — The number above the fraction bar that counts selected parts.
- denominator — The number below the bar showing equal parts in a whole.
- fraction bar — The horizontal line separating numerator and denominator.
- unit fraction — A fraction with numerator one, such as 1/5.
- half of a whole — One of two equal parts.
- third of a whole — One of three equal parts.
- fourth of a whole — One of four equal parts.
- fifth of a whole — One of five equal parts.
- eighth of a whole — One of eight equal parts.
- equal-size parts — Pieces of a whole that have the same area or amount.
- fraction strip — A rectangular model divided into equal fractional pieces.
- fraction circle — A circle model divided into equal sectors.
- shade the fraction — Colour the portion named by a fraction.
- unshaded part — The portion of a model not coloured.
- like fractions — Fractions that have the same denominator.
- compare unit fractions — Recognise that one of more equal pieces is smaller.
- compare like fractions — Compare numerators when the denominators match.
- add like fractions — Combine numerators while keeping the common denominator.
- subtract like fractions — Remove numerator parts while preserving the shared denominator.
5. Dollars, cents and decimal money notation — words 81–100
- dollars and cents — Two currency units written together in an amount.
- money notation — The conventional way to write currency amounts.
- decimal point in money — The dot separating whole dollars from cents.
- two decimal places in money — Writing cents with two digits after the dot.
- price tag — A label displaying an item’s selling price.
- receipt — A written record of items bought and prices paid.
- cashier — The person or point at which payment is taken.
- bill — A statement of the amount to pay.
- change — Money returned when the amount paid exceeds the price.
- amount tendered — The money handed over to pay a bill.
- exact payment — Giving precisely the amount required.
- overpayment — Giving more money than the listed price.
- underpayment — Giving less than the amount required.
- remaining cash — Money still in hand after spending.
- total cost — The sum of the prices of all selected items.
- difference in price — How much dearer one item is than another.
- convert dollars to cents — Express the same money amount entirely in cents.
- convert cents to dollars — Write cents as the equivalent dollar-and-cent amount.
- money comparison — Decide which of two or three amounts is greater.
- shopping budget — An amount available to spend in a simple shopping problem.
6. Length, mass and liquid volume — words 101–120
- metre — A metric unit of length suitable for longer objects.
- m — The abbreviation for metre.
- mass — A measure of the amount of matter in an object.
- gram — A metric unit of mass for relatively light things.
- g — The abbreviation for gram.
- kilogram — A metric unit of mass equal to 1,000 grams.
- kg — The abbreviation for kilogram.
- weighing scale — A device used to measure mass.
- heavier — Having greater mass when compared.
- lighter — Having less mass when compared.
- litre — A unit of capacity commonly used for liquids.
- L — A symbol used here for litre.
- liquid volume — How much space a liquid occupies.
- measuring jug — A marked container used to measure liquid volume.
- container capacity — The amount a container can hold.
- full container — A container holding its intended capacity.
- empty container — A container containing none of the measured liquid.
- half-full container — A container filled to about half its capacity.
- appropriate unit — A measurement unit suitable for the quantity.
- measurement comparison — Decide which measured length, mass or volume is greater.
7. Minutes, hours and elapsed time — words 121–140
- minute — A time interval equal to sixty seconds.
- clock face — The round display bearing hour and minute markings.
- minute mark — One minute division on the clock.
- quarter past — Fifteen minutes after the hour.
- quarter to — Fifteen minutes before the next hour.
- minutes after — How far a time has progressed beyond the hour.
- minutes before — How much time remains until the next hour.
- time to the minute — A clock reading that identifies a specific minute.
- hour interval — A time span lasting sixty minutes.
- elapsed time — The amount of time between the start and finish.
- starting time — The clock time when an event begins.
- finishing time — The clock time when an event ends.
- earlier time — The time that occurs first.
- later time — The time that occurs afterwards.
- hours to minutes — Rewrite an hours-and-minutes duration in minutes.
- minutes to hours — Express a number of minutes as hours and leftover minutes.
- sixty minutes — The duration of one hour.
- ninety minutes — One hour and thirty minutes.
- time schedule — A list of events and when they take place.
- clock reading — The time shown by the hands or digits on a clock.
8. Solid shapes, surfaces and orientation — words 141–160
- three-dimensional — Having length, width and height.
- solid shape — A three-dimensional object rather than a flat figure.
- cube — A solid with six equal square faces.
- cuboid — A solid with six rectangular faces; a cube is a special case.
- cone — A solid with a circular base narrowing to one point.
- cylinder — A solid with two circular bases joined by a curved surface.
- sphere — A round solid whose points are equally distant from its centre.
- flat face — A planar surface of a solid.
- curved surface — A surface that bends rather than lying flat.
- solid edge — Where two faces meet along a boundary.
- solid vertex — A corner point of a polyhedron.
- top view — How a shape appears when seen from above.
- front view — How a shape appears when seen from the front.
- side view — How a shape appears when seen from the side.
- orientation — The direction in which an object is positioned.
- rotate an object — Turn a solid while keeping its shape unchanged.
- stackable — Able to be placed in a stable pile.
- rollable — Able to move by rolling on a suitable surface.
- face shape — The two-dimensional figure seen on one flat face.
- classify solids — Sort three-dimensional shapes by their properties.
9. Patterns and scaled picture graphs — words 161–180
- repeating shape unit — The smallest group of shapes that repeats in a pattern.
- alternating colours — Two colours taking turns in a repeated pattern.
- alternating sizes — Sizes changing back and forth by a rule.
- pattern rule — The relationship that determines what comes next.
- pattern extension — Continue a given arrangement according to its rule.
- missing shape — A blank position whose correct figure must be inferred.
- orientation change — A rotation or direction difference in a shape pattern.
- shape attribute — A property such as colour, size or orientation.
- scaled picture graph — A picture graph where one picture can represent multiple items.
- graph key — A note telling what one picture symbol represents.
- one picture equals two — A graph convention that makes each picture count as two.
- half picture symbol — Half of the symbol’s stated value when the graph permits it.
- graph scale — The numerical value assigned to each symbol.
- represented total — How many actual items the graph’s symbols stand for.
- symbol count — How many pictures appear before applying the scale.
- category total — The actual quantity shown for one labelled group.
- difference between categories — Subtract two represented totals.
- graph interpretation — Answer questions by using the key and comparing values.
- graph evidence — The displayed numbers or pictures supporting an answer.
- check the key first — A reminder to avoid assuming each symbol equals one.
10. P2 word-problem commands and mathematical reasoning — words 181–200
- how much altogether — Ask for the combined value of named amounts.
- how much change — Ask how much money comes back after payment.
- how long did it take — Ask for the elapsed duration of an event.
- at the beginning — Describe the value before a change took place.
- at the end — Describe the value after the change.
- after receiving — Indicate that a quantity has been gained.
- after giving away — Indicate that a quantity has been reduced.
- how many each — Ask for the size of one equal share.
- how many groups — Ask for the number of equal collections.
- multiply to find total — Choose multiplication when equal group size and count are known.
- divide to share — Choose division when a total is split equally.
- fraction remaining — Ask what equal portion is left after taking some parts.
- complete the sentence — Fill in the missing value in an equation.
- fill in the blank — Write the number or word that makes the statement correct.
- draw an array — Show equal groups as rows and columns.
- write a division sentence — Express an equal-sharing or grouping situation symbolically.
- use the unit — Attach dollars, kilograms, litres or minutes to an answer as needed.
- is the answer reasonable — Check that the size and units fit the story.
- explain the method — Say why the chosen calculation matches the given relationships.
- independent check — Verify a result using another representation or operation.
Six worked examples: from a word to a decision
1. Place value: what does 523 mean?
Five hundreds, two tens and three ones make 523. Model it with five hundred-blocks, two ten-rods and three unit cubes. Ask, “What would happen if I exchanged one hundred for ten tens?” The represented number stays 523. A child who understands the exchange can later regroup accurately in vertical addition and subtraction. Do not teach carrying as a rule without its place-value meaning.
2. Addition and subtraction: why the columns matter
Suppose a library has 268 books and receives 145 more. Align the ones, tens and hundreds. First add 8 + 5 = 13 ones, write 3 and regroup one ten. Tens become 6 + 4 + 1 = 11 tens, so regroup one hundred. Hundreds become 2 + 1 + 1 = 4. The library has 413 books. A check is 413 − 145 = 268. The operations support each other; the check is evidence, not decoration.
3. Multiplication and division: read “each” carefully
There are four packets containing five crayons each. Total crayons: 4 × 5 = 20. Now give 20 crayons equally to five pupils. Each gets 20 ÷ 5 = 4. In the first problem, “each” identifies the group size; in the second, “each” names the unknown amount per pupil. A learner should be able to draw four rows of five and then five groups of four.
4. Fractions: the denominator names the size of the parts
A cake is cut into eight equal slices. Two slices are eaten and three more are eaten. The fraction eaten is 2/8 + 3/8 = 5/8. The eight does not turn into sixteen: the pieces are still eighths of the same cake. The remaining fraction is 3/8. If slices are unequal, describing them as equal eighths is not justified. Build equal parts before teaching a notation shortcut.
5. Money and time: two kinds of units
A notebook costs $3.40 and a child pays $5.00. The change is $1.60; the same calculation can be made as 500 cents − 340 cents = 160 cents. Now consider a lesson from 2:15 pm to 3:05 pm. Count 45 minutes to 3:00 pm, then 5 minutes more. Duration is 50 minutes. Money and time problems both need careful unit choices, but they are not interchangeable systems.
6. A scaled picture graph: one picture may not mean one
A class graph shows four book pictures under “fiction” and three under “science”. The key says one book picture represents two books. Fiction has 8 books, science has 6, and the difference is 2. If the child replies “one more,” the arithmetic may be correct for pictures but incorrect for the quantity represented. Point to the key and ask what each symbol is worth before calculating.
What makes Primary 2 Mathematics different from Primary 1?
Primary 1 builds number meaning, tens and ones, simple operations, measurement with centimetres and unscaled picture graphs. Primary 2 enlarges the number system to 1,000, adds hundreds, makes multiplication tables systematic, introduces simple fractions and asks pupils to read larger or scaled representations. The ideas are connected rather than separate chapters: understanding equal shares prepares fractions, while understanding place value prepares regrouping.
The jump is often linguistic before it is computational. “Five in each packet” and “five packets” sound similar but point to different relationships. “Half of a cake” requires equal parts; “half of a picture” only makes mathematical sense after deciding what the picture represents. Accurate wording helps children see what the story actually says.
Seven common errors and how to repair them
- Misreads 406 as forty-six: Use a hundreds–tens–ones chart and preserve the zero tens.
- Misaligns column addition: Place the digits over labelled columns before calculating.
- Memorises a times table but cannot share: Use physical groups and connect one multiplication fact to two division facts.
- Adds the denominators: Cut equal paper strips and name the size of each part before counting selected parts.
- Thinks $4.5 means $4.05: Show that $4.50 is four dollars and fifty cents and always write two digits for cents.
- Reads 2:45 to 3:15 as 70 minutes: Cross the hour boundary using a timeline: 15 minutes plus 15 minutes.
- Ignores the graph key: Ask the child to say aloud how many real objects each symbol represents.
How to teach words so that children can use them independently
Do not hand a child a sheet of 200 definitions for copying. Choose an active set of five to eight words from the school topic, especially terms that alter how a question is solved. Use the sequence point → model → say → calculate → explain → vary. A parent might model $2.40 as two dollar coins and forty cents, ask for a second way to make the same amount, and then ask a shopping question with a different price. By the third variation, the child should begin selecting the method without prompting.
Revisit the same word across contexts. “Difference” can describe a comparison in the number system, the price gap between two items or a gap in graph totals. The surface details differ, but the mathematical action is stable. This is how vocabulary supports abstraction instead of becoming a separate memory chore.
Four-week P2 Maths vocabulary plan for home
Week 1: Hundreds, tens and ones
Make and rename three-digit numbers, then add and subtract using place-value blocks. Have the child explain every exchange. Spend about ten to fifteen minutes per session and stop when explanation is still clear.
Week 2: Equal groups and fractions
Build arrays for the times tables of 2, 3, 4, 5 and 10. Share counters in two different ways. Fold strips into equal halves, thirds, quarters and eighths; ask why the pieces must be equal.
Week 3: Money, mass, volume and time
Use price tags and play-shop exchanges; compare objects on a weighing scale; pour water into marked containers; read start and finish times on a practice clock. Keep a single unit attached to every answer.
Week 4: Solids, patterns and graphs
Sort household objects by their 3D shape, rotate them and describe their surfaces. Make one picture graph where every symbol represents two objects and ask three different questions about it. Invite the child to check the graph key unaided.
How to know what needs help next
Look for the first incorrect step, not only the final mark. If the child can compute 7 × 4 but cannot decide when a packet question asks for multiplication, the issue is not just times-table recall. If the child understands halves of a folded strip but not of a differently oriented picture, the issue is transfer. Match the next lesson to this starting position; sign up for Mathematics tuition only after that position is clear.
Frequently asked questions
Do P2 children need to know decimals?
They read and write dollars and cents in decimal notation. The broader formal decimal place-value topic is taught later; do not confuse money notation with an unrestricted decimals syllabus.
Which multiplication tables are in P2?
The October 2025 MOE syllabus names the 2, 3, 4, 5 and 10 times tables. Pupils should connect facts to equal groups and division, rather than rely on chants alone.
Should a child already know equivalent fractions?
Primary 2 introduces fractions of a whole and operations with like fractions. Equivalent-fraction work is developed more formally in Primary 3. Strong equal-part reasoning is the right preparation.
Is a scaled picture graph harder than an ordinary picture graph?
It adds one critical interpretation: a picture can stand for more than one object. Read the key first, then calculate category totals using the scale.
How many words should we teach in a week?
Use only as many as the child can understand, explain and apply. A smaller set used correctly in unfamiliar problems is better than a long list recited without meaning.
Next reading and authoritative sources
Review the Primary 1 Mathematics 200-word foundation, the P2 vocabulary and concept companion, the eduKate guide to the MOE P1–P6 Mathematics syllabus, and the official updated MOE Mathematics syllabus. These links allow readers to check what is required and return to the most relevant explanation without searching through unrelated worksheets.