Mathematics

In this unit, children grow their number sense from 200 (in Grade 2) all the way to 1000, and take big steps with fractions through fair sharing.

They learn to count to 1000, including by 25s, 50s, 100s and 200s, forward and backward from any number; read and write numbers to 1000 in numerals and words and describe how numbers are used in everyday life; use place value with hundreds, tens and ones; compose and decompose numbers in many ways; compare and order numbers; and round to the nearest ten and hundred.

Then they solve fair-share problems with up to 20 items and 2, 3, 4, 5, 6, 8 or 10 sharers, finding shares that are whole numbers, mixed numbers and fractions (including the new fifths, eighths and tenths). They compare shares and discover equivalent fractions in three families: halves, fourths and eighths; thirds and sixths; fifths and tenths.

Along the way, children practise the social-emotional skills and mathematical processes of Strand A: sticking with a problem, explaining their thinking, checking their work and being fair. Each lesson includes worked examples, pictures, a hands-on activity with things from home, practice questions with answers, a short quiz and notes for the grown-up helping.

Curriculum expectations covered: B1.1, B1.2, B1.3, B1.4, B1.5, B1.6, B1.7, with A1 woven in (Ontario Mathematics, Grade 3, 2020).

In this unit you will grow into a powerful math thinker! First you will use mental math and estimation with numbers up to 1000. Then you will add and subtract three-digit numbers, connecting base-ten blocks to the column method (an algorithm), and solve all kinds of story problems. Next you will learn the × and ÷ signs: multiplying and dividing with equal groups, arrays and number lines up to 10 × 10 and 100 ÷ 10, and using math rules like any order and splitting. You will learn your multiplication and division facts of 2, 5 and 10 by heart, solve multiplication and division problems, work with groups of halves, thirds and fourths (like 1/4 + 1/4 + 1/4 = 3/4), and use ratios of 1 to 2, 1 to 5 and 1 to 10 to scale up.

Remember from Grade 2: you added and subtracted to 100, made equal groups and shared fairly. Grade 3 builds on all of it. Every lesson has hands-on activities you can do at home, lots of practice and a short quiz.

Curriculum expectations covered: B2.1, B2.2, B2.3, B2.4, B2.5, B2.6, B2.7, B2.8, B2.9, with A1 (social-emotional learning skills and mathematical processes) woven in (Ontario Mathematics, Grade 3, 2020).

In this unit, Grade 3 students build on the patterns, variables, coding and modelling they learned in Grade 2, with bigger numbers and new tools.

• Patterns and relationships (C1): find what repeats in a pattern (a core of elements, an operation like add 4, or a movement like a quarter turn); create and translate patterns using shapes, numbers and tables of values; use pattern rules to extend, predict and find missing elements; and create number patterns to 1000.
• Equations and inequalities (C2): use variables for unknown numbers and for amounts that change; decide whether expressions with adding, subtracting, multiplying and dividing are equivalent (= or ≠); and show numbers to 1000 in equivalent ways, including with money and length.
• Coding (C3): write, run, read, change and debug code with sequential, concurrent and repeating events (loops).
• Mathematical modelling (C4): use the steps understand, assume, model, check and share to plan real-life events like a skating party or a field trip.

Throughout the unit, children practise explaining their thinking, working with others and keeping going when something is hard (Strand A).

Curriculum expectations covered: C1.1, C1.2, C1.3, C1.4, C2.1, C2.2, C2.3, C3.1, C3.2, C4, with A1 (social-emotional learning skills and the mathematical processes) woven in (Ontario Mathematics, Grade 3, 2020).

In this unit, Grade 3 data detectives sort data about people and things by two and three attributes using Carroll diagrams, Venn diagrams (including three circles) and tree diagrams. They collect qualitative and quantitative data through interviews, observations and experiments and organize it in frequency tables. They display data with many-to-one correspondence in pictographs (with a key) and bar graphs (with scales that count by 2s, 5s or 10s), including titles, labels and sources. They find the mean (as a fair share) and the mode(s), explain what each tells us, and analyse data in tables and in graphs with different scales to draw conclusions, make convincing arguments and informed decisions.

The unit ends with probability: describing events as impossible, unlikely, equally likely, likely or certain to make predictions and decisions, and predicting and testing whether a different population will have the same mean and mode. Explaining thinking, listening to others and reflecting on predictions (Strand A) are woven through every lesson.

Curriculum expectations covered: D1.1, D1.2, D1.3, D1.4, D1.5, D2.1, D2.2, with A1 (Ontario Mathematics, Grade 3, 2020).

In this unit you will become a 3D object expert, a direction giver and a measuring pro!

In geometry, you will describe cubes, prisms, pyramids, cylinders and cones by their faces, edges, vertices and angles, sort them and build them. You will find the 3D objects and 2D shapes inside structures, including the Inuit inuksuk, and find congruent faces, edges and objects. You will give and follow directions with distances and quarter and half turns.

In measurement, you will find perimeter, learn how millimetres, centimetres, metres and kilometres are related, measure capacity with cups and scoops and mass with a pan balance, tell time to the minute on analog and digital clocks and timers, and measure area with non-standard units and with square centimetres and square metres.

Remember from Grade 2: you sorted 2D shapes, read simple maps, measured in centimetres and metres, and read o'clock and half-past times. Grade 3 builds on all of these. Every lesson has hands-on activities you can do at home, lots of practice and a short quiz.

Curriculum expectations covered: E1.1, E1.2, E1.3, E1.4, E2.1, E2.2, E2.3, E2.4, E2.5, E2.6, E2.7, E2.8, E2.9, with A1 (social-emotional learning skills and mathematical processes) woven in (Ontario Mathematics, Grade 3, 2020).

In Grade 2, children counted Canadian coins and bills and found different ways to pay exactly. In Grade 3 they learn what happens when you pay more than the price: you get change. They find the change for simple cash purchases with whole-dollar prices (paying with $5, $10 or $20 bills) and with prices less than one dollar (paying with a loonie or a few quarters). They count up like a cashier, use adding facts and pairs that make 10 and 100, estimate change with friendly numbers, find change for two or three items, give change with the fewest coins, and check change with price + change = money paid.

Because Canada no longer uses pennies, cash totals are rounded to the nearest 5¢, and every price in this unit ends in 0 or 5. Amounts under a dollar are written in cents (65¢); decimal notation comes in later grades.

Curriculum expectations covered: F1.1 (Ontario Mathematics, Grade 3, 2020), with the social-emotional learning skills and mathematical processes (A1) woven through.