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Curriculum series · Grade 8

Ontario Grade 8 Math

Every big idea in Ontario's Grade 8 math curriculum, in one place. If your child is stuck on something, find it here: ideas with a lesson open an interactive page they can drag, slide and play with. The rest are on the way.

14 of 40 ideas have a lesson

Also: Ontario Grade 4 Math

Number3/12
Algebra5/8
Data1/6
Spatial Sense5/13
Financial Literacy0/1

Ready to play

In curriculum order. Tick a lesson once your child has done it; ticks stay in this browser only.

Every idea

Grouped by curriculum strand. A filled dot means there is a lesson.

B Number3 / 12 with a lesson

  • Scientific notationComing soonB1.1 · E2.13 × 10⁶ doesn't make you count zeros: the exponent just says how many places the digits slide.
  • Multiplying by 10, 100 and 1000Why isn't ×10 just "add a 0"?B2.3Multiplying by 10 moves every digit one place to the left; 'add a zero' is only a shortcut, and it breaks for decimals.
  • Square rootsRadicals Unpacked — The Radical LabB1.3 · B2.2√49 asks one question: what side length makes a square with area 49?
  • Irrational numbersComing soonB1.2 · C1.4√2 is a real length you can draw, yet no fraction lands exactly on it, so its decimals never stop or repeat.
  • PercentComing soonB1.4Percent means 'out of 100', so 150% is one and a half wholes and 0.5% is half of one hundredth.
  • Adding and subtracting integersComing soonB2.4A positive and a negative cancel to zero, so subtracting a negative is like taking away a debt: you end up higher.
  • Multiplying and dividing integersComing soonB2.7Multiplying by −1 turns you around on the number line; turn around twice and you face forward again, so negative × negative is positive.
  • Adding and subtracting fractionsComing soonB2.5You can only add pieces of the same size, so first cut both fractions into matching pieces.
  • Multiplying fractionsComing soonB2.61/2 of 2/3 is a rectangle inside a rectangle: the overlap is the answer.
  • Dividing fractionsComing soonB2.63 ÷ 1/4 asks how many quarters fit in 3; each whole holds 4, so the answer is 3 × 4.
  • Properties of multiplicationWhy does 7 × 13 equal 70 + 21?B2.1Turning, regrouping or splitting an array never changes how many squares it holds; that is why order, grouping and splitting don't change a product.
  • Proportional reasoningComing soonB2.1 · B2.8 · E1.3Equal ratios scale together: double one side and the other doubles too.

C Algebra5 / 8 with a lesson

  • Repeating and growing patternsDoes a pattern repeat or grow?C1.1A repeating pattern cycles through the same core; a growing pattern changes by a rule at every step.
  • One pattern, many representationsShapes, table, graph: one pattern?C1.2The same growing pattern can be drawn as shapes, written as a table of values, or plotted as points on a graph.
  • Linear patternsComing soonC1.1 · C1.2 · C1.3A linear pattern is a starting value plus the same step every time; the step is the rate of change.
  • VariablesWhat does the letter stand for?C2.2A letter or symbol holds the place of a number we don't know yet.
  • Combining like termsComing soonC2.13x + 2x = 5x for the same reason 3 apples + 2 apples = 5 apples, and x + 3 can't merge any more than apples and oranges.
  • Equations as balanceWhat does the = sign really mean?C2.3An equation is a balance: do the same thing to both sides and it stays level.
  • InequalitiesHow many answers can □ + 3 < 10 have?C2.4An inequality's answer is not one number but a whole stretch of the number line.
  • Code that analyses dataComing soonC3.1 · C3.2A loop lets code do to a thousand rows what you would do to one, so changing one line changes every result.

D Data1 / 6 with a lesson

  • Kinds of data and choosing a graphCan a graph lie about pets?D1.3Data is either measured and counted (quantitative) or sorted into categories (qualitative), and the graph has to fit the kind of data.
  • Two-variable dataComing soonD1.1 · D1.3Each dot on a scatter plot is one thing measured two ways; together the dots show whether the two measures move together.
  • CorrelationComing soonD1.5 · D1.6Two measures can rise together without one causing the other; a third thing may be pushing both.
  • Misleading graphsComing soonD1.6The same numbers can look huge or tiny depending on where the axis starts, so a graph can mislead without a single false number.
  • Compound eventsComing soonD2.1 · D2.2Each branch of a tree diagram splits every outcome before it, so probabilities along a path multiply.
  • Experimental vs theoretical probabilityComing soonD2.2Ten flips can look wild, but a thousand settle close to the theory: more trials, less surprise.

E Spatial Sense5 / 13 with a lesson

  • TessellationsComing soonE1.1Shapes tile a floor with no gaps exactly when the angles meeting at each corner add to 360°.
  • Views of 3D objectsComing soonE1.2A top view, a front view and a side view together pin down a 3D object; one view alone can hide things.
  • Scale factor and areaComing soonE1.3Stretch every length by k and the area grows by k × k, so doubling a map makes it four times bigger.
  • Translations and reflectionsFlip and slide: fit the shadowE1.4Sliding or flipping a shape changes where it is, never its size or shape.
  • DilationsComing soonE1.4Dilating from the origin multiplies every coordinate by the same number, so the shape keeps its angles but changes size.
  • Angles and parallel linesComing soonE2.2A line crossing two parallel lines makes the same set of angles twice, which is why alternate and corresponding angles match.
  • Angle sum of polygonsComing soonE2.2Any polygon with n sides cuts into n − 2 triangles, so its angles add to (n − 2) × 180°.
  • Metric units and prefixesZoom from a kilometre to a millimetreE2.1Kilo means a thousand and milli means a thousandth: the same base-ten trade as place value.
  • Circumference and πτ — one full turnE2.3π is how many diameters it takes to wrap around any circle, big or small: always a little more than 3.
  • Area of a circleWhy is a circle's area πr²?E2.3Cut a circle into thin wedges and line them up: they make a rectangle πr long and r tall, so the area is πr².
  • Volume of prisms and cylindersComing soonE2.3A prism is the same slice stacked up, so its volume is the area of the base times the height.
  • Surface areaComing soonE2.3Unfold a box flat and its surface area is just the area of that net.
  • Pythagorean theoremWhy does 3-4-5 work?E2.4Rearrange four copies of a right triangle inside one big square and the hole changes from c² into a² + b².

F Financial Literacy0 / 1 with a lesson

  • Compound interestComing soonF1.4Interest earns its own interest, so the money doesn't grow in a straight line: it curves upward.
Practised inside lessons, not separate pages

These expectations are about speed and fluency with an idea above. They show up as practice in that idea's lesson.

  • B2.1 Use properties, order of operations and links between operations to solve multi-step problems with rational numbers, ratios, rates and percents.
  • B2.2 Know common square numbers and their square roots.
  • C1.3 Use pattern rules to extend patterns, predict, find missing terms, and solve for unknowns in linear patterns.
  • C2.2 Evaluate algebraic expressions with rational numbers.
  • C3.2 Read and change existing data-analysis code, and describe how the changes affect results and efficiency.
Not covered here

These are projects, process skills or everyday money knowledge. They don't have a single "why" to take apart, so we leave them to the classroom.

  • C4.1 Apply the mathematical modelling process to real-life situations.
  • D1.2 Collect continuous two-variable data and organize it in tables of values.
  • D1.4 Create an infographic that tells a data-driven story.
  • F1.1 Weigh payment methods when dealing with several currencies and exchange rates.
  • F1.2 Make a financial plan for a long-term goal, including income, expenses and taxes.
  • F1.3 Keep a budget balanced and track income and spending.
  • F1.5 Compare ways to get more value for money, such as sales and loyalty programs.
  • F1.6 Compare credit card interest rates, fees and rewards to find the best option.