Grade 9 Math: how to help at home
What your child learns in Grade 9 math in the Ontario Curriculum, and simple things to try at home.
The Big Ideas this year
- AA1 Social-Emotional Learning Skills: Develop and explore a variety of social-emotional learning skills in a context that supports and reflects this learning in connection with the expectations across all other strands
- A1 Mathematical Processes: Apply the mathematical processes to develop a conceptual understanding of, and procedural fluency with, the mathematics they are learning
- A2 Making Connections: Make connections between mathematics and various knowledge systems, their lived experiences, and various real-life applications of mathematics, including careers
- B1 Development of Numbers and Number Sets: Demonstrate an understanding of the development and use of numbers, and make connections between sets of numbers
- B2 Powers: Represent numbers in various ways, evaluate powers, and simplify expressions by using the relationships between powers and their exponents
- B3 Number Sense and Operations: Apply an understanding of rational numbers, ratios, rates, percentages, and proportions, in various mathematical contexts, and to solve problems
- C1 Algebraic Expressions and Equations: Demonstrate an understanding of the development and use of algebraic concepts and of their connection to numbers, using various tools and representations
- C2 Coding: Apply coding skills to represent mathematical concepts and relationships dynamically, and to solve problems, in algebra and across the other strands
- C3 Application of Relations: Represent and compare linear and non-linear relations that model real-life situations, and use these representations to make predictions
- C4 Characteristics of Relations: Demonstrate an understanding of the characteristics of various representations of linear and non-linear relations, using tools, including coding when appropriate
- D1 Collection, Representation, and Analysis of Data: Describe the collection and use of data, and represent and analyse data involving one and two variables
- D2 Mathematical Modelling: Apply the process of mathematical modelling, using data and mathematical concepts from other strands, to represent, analyse, make predictions, and provide insight into real-life situations
- E1 Geometric and Measurement Relationships: Demonstrate an understanding of the development and use of geometric and measurement relationships, and apply these relationships to solve problems, including problems involving real-life situations
- F1 Financial Decisions: Demonstrate the knowledge and skills needed to make informed financial decisions
Easy ways to practise math at home
- Look for fractions, decimals and percentages in sale signs, sports statistics and recipes.
- Ask your child to explain a problem to you as if you were the student.
- Estimate first (the bill, the trip time), then check with a calculator.
- Keep a tricky-problems list and revisit it every few days instead of re-doing everything.
What each unit covers
Number Sets
Natural numbers, whole numbers, integers, rational and irrational numbers, how they fit inside each other, and why there are always more numbers between any two rational numbers.
Rational Numbers
Adding, subtracting, multiplying and dividing fractions and decimals that may be negative, converting between fractions and decimals, ordering rational numbers, and using BEDMAS.
Powers & Scientific Notation
Patterns that show why a power to the zero is 1 and a negative exponent makes a reciprocal, and writing very large and very small numbers in scientific notation.
Exponents & Powers
Evaluating powers, using the product, quotient and power laws, working with powers of products and fractions, and order of operations with exponents.
Rates & Percents
Unit rates and best buys, percent of an amount, percent increase and decrease, proportions in ratios, and negative rates such as a diver going down.
Expressions
Writing an expression for a pattern or a sentence, deciding which expressions are equivalent, expanding brackets, and collecting like terms.
Polynomials
Naming polynomials by terms and degree, combining like terms, subtracting polynomials, multiplying and dividing by a constant, and substituting values for x.
Multi-Step Equations
Solving linear equations with brackets, fractions and variables on both sides, checking solutions, and turning word problems into equations.
Code Reader
Reading short programs with variables, loops, if statements and functions, predicting the output, and changing a parameter to get a new result. No typing is needed; the code is written in plain pseudocode.
Linear Relations
Finding slope from points and graphs, reading y = mx + b, finding intercepts, deciding whether a point is on a line, spotting parallel lines, and using rates of change in stories.
Lines & Intersections
Finding where two lines meet and what it means in a story, graphing x = k, y = k and ax + by = k, regions of an inequality, and translating, reflecting and rotating lines through the origin.
Data & Scatter Plots
Finding the median and quartiles of a data set, reading a box plot, telling positive, negative and no correlation apart, and using a line of best fit to make predictions. Correlation does not prove one thing causes another.
Right Triangles & Scaling
Using the Pythagorean relationship for ladders, ramps, roofs and diagonals, deciding whether a triangle is right-angled, and seeing how doubling or tripling dimensions changes perimeter, area and volume.
Volume & Units
A pyramid holds a third of the matching prism and a cone a third of the matching cylinder, plus converting between metric units and between metric and imperial units.
Money Decisions
Items that gain or lose value over time, simple and compound interest, how rate, time and down payments change the cost of borrowing, adjusting a budget, and adding 13% HST.
What the report card levels look like at home
- Level 1
- Just getting started with this idea. Short, regular practice with lots of support helps most.
- Level 2
- Understands parts of it and is building confidence. Keep practising the tricky parts.
- Level 3
- Has it! Level 3 is the provincial standard. Mixed review now and then keeps it strong.
- Level 4
- Applies it confidently, even in new or harder situations. Try challenge mode and real-life problems.
Your child’s teacher decides the level on the report card. Read the Ontario report card guide.
Common questions
How can I help my Grade 9 child with math?
Look for fractions, decimals and percentages in sale signs, sports statistics and recipes. Ask your child to explain a problem to you as if you were the student. Keep sessions short, about 10 to 15 minutes, and stop on a success.
What does my child learn in Grade 9 math in Ontario?
The Ontario Curriculum Grade 9 math units include number sets, rational numbers, powers & scientific notation, exponents & powers, rates & percents, expressions.
Free printable Grade 9 math practice sheet
Questions from every unit, with an answer key.