Students build on their understanding of number lines to construct a coordinate system composed of intersecting horizontal and vertical number lines. Students plot points and identify ordered pairs for points. They describe the location of a point in the coordinate plane as a horizontal distance from the y-axis and a vertical distance from the x-axis. Students conclude the topic by using a map on a coordinate plane to identify locations and describe distances and directions between those locations. 

Family Math Topic A

Students extend their understanding of the coordinate plane by identifying properties of horizontal and vertical lines in the coordinate plane. Students then work with two number patterns simultaneously, generating terms when given rules and starting numbers, using the patterns to create ordered pairs, and plotting the points that represent the ordered pairs. Students transition to using tables and graphs to examine relationships between corresponding terms in two number patterns. They identify, describe, and compare addition, subtraction, multiplication, and division number relationships in the coordinate plane. Topic B ends with an optional lesson in which students identify and describe mixed-operation number patterns. 

Family Math Topic B

Students begin topic C by examining lines in the coordinate plane. They develop the understanding that lines have an infinite number of points. They realize that one point has many lines through it, but any two points can have only one line that passes through them both. Then students work with geometric figures in the coordinate plane. They classify angles, identify parallel and perpendicular line segments, and use those observations to classify quadrilaterals graphed in the coordinate plane. Students identify lines of symmetry and look for patterns in the coordinates of symmetric points. At the end of the topic, students solve problems by drawing rectangles in the coordinate plane and determining their vertices, perimeters, and areas. 

Family Math Topic C

In topic D, students recognize that the coordinate plane is a useful tool for representing data, modeling relationships, and solving real-world problems. They come to understand that graphs can tell stories. Students interpret the meaning of points and line segments in a line graph that represents real-world data. In both an optional lesson and a real-world problem-solving task, students revisit relationships between two number patterns. Students solve problems by using a graph to identify and describe the number patterns in the x- and y-coordinates. 

Family Math Topic D

axes

Axes are the pair of perpendicular number lines that create a coordinate system. Axes refers to both the x-axis and the y-axis together. (Lesson 2)

coordinate

A coordinate is a number used to identify the location of a point. (Lesson 1)

coordinate plane

A coordinate plane is a plane with a coordinate system used to describe locations of points in the plane. A coordinate plane has perpendicular axes that intersect at 0. (Lesson 2)

coordinate system

A coordinate system is a system that uses one or more numbers, or coordinates, to identify the location of a point. (Lesson 1)

ordered pair

An ordered pair is a pair of two coordinates that describe the location of a point in the coordinate plane. An ordered pair is written (x, y), where x represents the point’s x-coordinate and y represents the point’s y-coordinate. (Lesson 2)

origin

The origin is the point where the x- and y-axes intersect. The origin is located at the point (0, 0). (Lesson 2)

x-axis

The x-axis is the horizontal number line in a coordinate system. (Lesson 2)

x-coordinate

The x-coordinate is the value that describes a point’s horizontal distance from the y-axis. (Lesson 2)

y-axis

The y-axis is the vertical number line in a coordinate system. (Lesson 2)

y-coordinate

The y-coordinate is the value that describes a point’s vertical distance from the x-axis. (Lesson 2)