Mathematics

In kindergarten through Grade 2, students had many experiences with numbers, building their understanding of the base-10 number system and how it works. In this unit, they will extend that work with addition and subtraction to the hundreds place.

In this unit, students work with telling time to the minute. They also compute how much time has elapsed between two events, and they think about why that matters. There are many real-world connections in this unit. One important aspect of time is that an hour is 60 minutes—unlike the groupings of 10s and 100s that are part of our base-10 system. Students must develop flexible thinking with a different grouping of numbers and units.

Grade 3 students spend a lot of time with multiplication and division strategies within 100. The foundational work they do to understand multiplication and division in Grade 3 will set them up to succeed with fractions throughout elementary school and ratios in middle school and high school. In this unit, students start by multiplying the numbers 2–9 by the numbers 2–5.

Students have been reasoning with shapes since preschool and kindergarten. In this unit, third graders work with shapes in different categories, with a particular focus on different types of quadrilaterals (also known as four-sided figures). They also extend their work with

shapes to include perimeter, or the length around the outside edge of a shape.

Third graders spend a lot of time with multiplication and division strategies within 100​. The foundational work they do to understand multiplication and division in 3rd grade will set them up for fractions through the end of elementary school and ratios through middle school into high school. This unit is very closely related to unit 3.3 Exploring Multiplication. Students worked on the smaller factors of 2 – 5 in unit 3. In this unit, students start by multiplying the numbers 2 - 9 by the numbers 6 - 9.

Third graders spend a lot of time with multiplication and division strategies within 100​. The foundational work they do to understand multiplication and division in 3rd grade will set them up for fractions through the end of elementary school and ratios through middle school

into high school. Third graders have now worked with factors 2 - 9. In this unit, they move on to seeing patterns in multiples of 10, and how the digit zero holds place value. They are continuing to build their fluency with multiplication. While speed should never be associated with being smart in math, you are likely to see that your child is getting more flexible with manipulating numbers, and

the many ways of putting them together and pulling them apart.

In third grade, students spend a lot of time with multiplication and division strategies within 100​. The foundational work they do to understand multiplication and division in 3rd grade will set them up for understanding of operations with fractions through the end of elementary school and ratios through middle school and into high school.

In this unit, third graders build on work they did in second grade to recognize and name fractions. They practice many strategies to understand, show, and compare fractions. Fractions are numbers between the whole numbers.

For example, the number 1⁄2 :

• describes each part of a shape that has been cut into 2 equal pieces;

• is the number exactly halfway between 0 and 1 on the number line.

1⁄2 is also an equal share of objects divided into 2 groups. This way of thinking of fractions, as parts of sets, will be emphasized in 4th grade and beyond.

Area​ and perimeter​ are attributes of 2-D figures. Area is the space inside a figure, and it can be found by counting the squares inside of a figure using tiles or a grid, or by using multiplication. Perimeter is the distance around a figure. In this unit, 3rd graders will learn how area and perimeter are related and how they are different.

Data are facts or information, and students have put data into categories since kindergarten. In this unit, 3rd graders continue to organize data in different ways to help them make sense of it. Third graders use the same kinds of graphs they used in second grade, with the difference that 3rd grade students now draw scaled graphs​. What this means is that 3rd graders show data in multiples, such as groups of 2, 5 or 10.

In this unit, third graders will work with standard units of measurement​ to measure volume and mass. They use standard measurements (i.e., measurements that are universally agreed upon, such as one gram or one liter), and decide what units to use based on the thing they are measuring. In this unit, students solve word problems about volume and weight using drawings, diagrams, and equations.

Students have spent much of 1st through 3rd grade building their understanding of the operations of addition, subtraction, and now multiplication and division. In this unit, students will make sense of real world problems the solution of which involves two steps by modeling them with diagrams and equations using a letter for the unknown value. As students learn to model and solve these problems, they ask themselves, What is this problem about? What is the part I am trying to find out? With every kind of situation, they ask, does my answer make sense? How do I know?

Third graders have been using the formal algebraic convention of representing unknown parts of an equation with a letter, such as 120 – n = 65. In this unit, students write equations with more than one operation, such as 4 x 5 + n = 26.