OS
OpenStem
@openstem · Joined Jul 2026
7420 public items8 groups
Flashcards8 cards
What is a repeating pattern?1 / 8
A repeating pattern uses the same small group of things over and over, in the same order — like red, blue, red, blue, red, blue.
Mathematics · L1 · Patterns: Repeating & Growing
@openstem
Mathematics · L1 · Patterns: Repeating & GrowingFlashcards10 cards
What word tells you someone finished FIRST in a race?1 / 10
1st. The runner who crosses the line before everyone else finished 1st.
Mathematics · L1 · Ordinal Numbers & Ordering
@openstem
Mathematics · L1 · Ordinal Numbers & OrderingFlashcards10 cards
What is a line of symmetry?1 / 10
A line of symmetry is an imaginary line that cuts a shape into two matching halves. If you fold the shape along that line, both sides land exactly on top of each other.
Mathematics · L1 · Symmetry & Reflection
@openstem
Mathematics · L1 · Symmetry & ReflectionFlashcards10 cards
What does 'double' mean?1 / 10
Double means 2 times as many. To double a number, add it to itself.
Mathematics · L1 · Doubling & Halving
@openstem
Mathematics · L1 · Doubling & HalvingFlashcards8 cards
What is a number line?1 / 8
A number line is a straight line with numbers marked at equal spaces, in order from smallest to biggest. It helps you see how far apart numbers are.
Mathematics · L1 · Number Lines & Rounding to Ten
@openstem
Mathematics · L1 · Number Lines & Rounding to TenFlashcards8 cards
12 sweets are shared equally between 3 friends. How many sweets does each friend get?1 / 8
Each friend gets 4 sweets. 12 ÷ 3 = 4. Sharing them out one at a time keeps it fair.
Mathematics · L1 · Fractions of a Group
@openstem
Mathematics · L1 · Fractions of a GroupFlashcards8 cards
How many sides does a triangle have?1 / 8
3 sides and 3 corners. "Tri" means three, just like a tricycle has 3 wheels.
Mathematics · L1 · 2D Shapes & Their Attributes
@openstem
Mathematics · L1 · 2D Shapes & Their AttributesFlashcards8 cards
What does it mean to cut a shape into 'equal parts'?1 / 8
Every part must be the exact same size as every other part. If the parts are different sizes, they are not equal parts.
Mathematics · L1 · Equal Parts: Halves, Thirds & Quarters
@openstem
Mathematics · L1 · Equal Parts: Halves, Thirds & QuartersFlashcards8 cards
What does 'capacity' mean?1 / 8
Capacity is how much a container can hold — like how much water fits inside a cup or a bucket.
Mathematics · L1 · Capacity & Volume: More, Less or Same
@openstem
Mathematics · L1 · Capacity & Volume: More, Less or SameFlashcards7 cards
How can you tell which of two pencils is longer without measuring?1 / 7
Line up one end of both pencils together on a flat surface. Whichever pencil sticks out further past the other one is longer.
Mathematics · L1 · Comparing Length: Longer, Shorter, Taller
@openstem
Mathematics · L1 · Comparing Length: Longer, Shorter, TallerFlashcards8 cards
What is a fact family?1 / 8
A fact family is a group of three numbers and the addition and subtraction facts you can make from them. For 4, 5, and 9, the fact family is 4+5=9, 5+4=9, 9-4=5, and 9-5=4.
Mathematics · L1 · Fact Families & Related Facts
@openstem
Mathematics · L1 · Fact Families & Related FactsFlashcards8 cards
What does it mean to "estimate" an amount?1 / 8
To estimate means to make a smart, reasonable guess about how many there are, without counting every single one.
Mathematics · L1 · Estimating & Benchmark Numbers
@openstem
Mathematics · L1 · Estimating & Benchmark NumbersFlashcards7 cards
Sam has 8 stickers. Ana has 5 stickers. How many more stickers does Sam have?1 / 7
3 more. Subtract the smaller amount from the bigger amount: 8 - 5 = 3.
Mathematics · L1 · Comparison Word Problems: More & Fewer
@openstem
Mathematics · L1 · Comparison Word Problems: More & FewerFlashcards7 cards
What do words like "first," "next," and "last" help us do?1 / 7
They are sequence words. They tell us the order that things happen in — what comes at the very start, what comes in the middle, and what comes at the very end.
Mathematics · L1 · Sequencing Events: First, Next, Last
@openstem
Mathematics · L1 · Sequencing Events: First, Next, LastFlashcards8 cards
What coin is small, copper-colored, and worth 1¢?1 / 8
The penny. It has a copper color and is worth one cent (1¢).
Mathematics · L1 · Coin Recognition & Values
@openstem
Mathematics · L1 · Coin Recognition & ValuesFlashcards5 cards
What is a negative number?1 / 5
A negative number is less than zero. On a number line, negative numbers sit to the left of zero. Temperature below freezing is a good real-life example: −5°C is 5 degrees below zero.
Mathematics · L2 · Integers and Negative Numbers
@openstem
Mathematics · L2 · Integers and Negative NumbersFlashcards5 cards
What does x mean in algebra?1 / 5
x is a placeholder for an unknown number. The goal is to find what number x must be to make the equation true.
Mathematics · L2 · Introduction to Algebra
@openstem
Mathematics · L2 · Introduction to AlgebraFlashcards5 cards
What is the mean of a set of numbers?1 / 5
The mean is the average. Add all the numbers together, then divide by how many numbers there are. For 2, 4, 6: add to get 12, divide by 3 = mean of 4.
Mathematics · L2 · Mean, Median, and Mode
@openstem
Mathematics · L2 · Mean, Median, and ModeFlashcards5 cards
What is probability?1 / 5
Probability tells us how likely something is to happen. We write it as a fraction, decimal, or percent.
Mathematics · L2 · Simple Probability
@openstem
Mathematics · L2 · Simple ProbabilityFlashcards8 cards
How do you add two fractions that already have the same denominator, like 2/9 + 4/9?1 / 8
Add the numerators (the top numbers) and keep the denominator the same. Then check if the answer can be simplified — here 6/9 reduces to 2/3.
Mathematics · L2 · Adding & Subtracting Fractions
@openstem
Mathematics · L2 · Adding & Subtracting FractionsFlashcards7 cards
What do a fraction, a decimal, and a percent all describe?1 / 7
The exact same amount, just written in three different forms. 1/2, 0.5, and 50% all mean the same part of a whole.
Mathematics · L2 · Decimals & Percents
@openstem
Mathematics · L2 · Decimals & PercentsFlashcards8 cards
What does each letter in PEMDAS stand for?1 / 8
PEMDAS is a memory trick for the order to solve a math expression with more than one operation.
Mathematics · L2 · Order of Operations
@openstem
Mathematics · L2 · Order of OperationsFlashcards8 cards
What does an exponent tell you to do?1 / 8
An exponent tells you how many times to multiply a number (the base) by itself. In 5³, the base is 5 and the exponent is 3, so you multiply 5 × 5 × 5.
Mathematics · L2 · Exponents & Square Roots
@openstem
Mathematics · L2 · Exponents & Square RootsFlashcards8 cards
What is a factor of a number?1 / 8
A factor is a whole number that divides another number exactly, with nothing left over. 4 is a factor of 12 because 12 ÷ 4 = 3 with no remainder.
Mathematics · L2 · Factors, Multiples & Primes
@openstem
Mathematics · L2 · Factors, Multiples & PrimesFlashcards8 cards
What is the range of a data set?1 / 8
The range tells you how spread out the data is. Range = biggest value − smallest value. It's the simplest way to measure spread.
Mathematics · L2 · Range, Outliers & Data Spread
@openstem
Mathematics · L2 · Range, Outliers & Data SpreadFlashcards8 cards
What is a two-way table used for?1 / 8
A two-way table organizes counts for two categories at once. For example, a survey could record each student's grade level (the rows) crossed with their favorite subject (the columns) — every cell shows how many students fit both categories.
Mathematics · L2 · Two-Way Tables & Venn Diagrams
@openstem
Mathematics · L2 · Two-Way Tables & Venn DiagramsFlashcards8 cards
What is a ratio, and name three ways to write one.1 / 8
A ratio compares two quantities. You can write it three ways: a:b, a/b, or "a to b". For 3 red marbles and 5 blue marbles, that's 3:5, 3/5, or "3 to 5".
Mathematics · L2 · Ratios & Unit Rates
@openstem
Mathematics · L2 · Ratios & Unit RatesFlashcards8 cards
What form does a two-step equation take, and what does that mean?1 / 8
A two-step equation looks like ax + b = c — a number multiplied by x, plus or minus another number, equals a total. To solve it you make exactly two moves: undo the addition or subtraction first, then undo the multiplication or division.
Mathematics · L2 · Two-Step Equations & Inequalities
@openstem
Mathematics · L2 · Two-Step Equations & InequalitiesFlashcards8 cards
What is the coordinate plane?1 / 8
A flat grid made from two number lines that cross at a right angle. It lets us describe the exact location of any point using two numbers.
Mathematics · L2 · The Coordinate Plane
@openstem
Mathematics · L2 · The Coordinate PlaneFlashcards8 cards
What formula do you use to find the volume of a rectangular prism (box)?1 / 8
V = length × width × height. Multiply all three dimensions together to find how much space fits inside.
Mathematics · L2 · Volume & Surface Area of Prisms
@openstem
Mathematics · L2 · Volume & Surface Area of Prisms