Grade 8 Mathematics
In grade eight, students take their understanding of unit rates and proportional relationships to a new level, connecting these concepts to points on a line and ultimately using them to solve linear equations that require them to apply algebraic reasoning as well as knowledge of the properties of operations. Students will also expand their understanding of numbers beyond rational numbers to include numbers that are irrational—meaning that they cannot be written as a simple fraction, such as the square root of 2 or √2 . Activities in these areas will include:
- Understanding that every rational number (such as ½, 0.3, 2, or -2) can be written as a decimal, but that the decimal form of an irrational number (such as √2 ) is both non-repeating and infinite
- Applying the properties of exponents to generate equivalent numerical expressions
- Determining the value of square roots of small perfect squares (such as √49= 7) and cube roots of small perfect cubes (such as ³√64=4)
- Graphing proportional relationships and interpreting the unit rate as the slope (how steep or flat a line is)
- Solving and graphing one- and two-variable linear equations
- Understanding that a function is a rule that assigns to each value of x exactly one value of y, such as y=2x, a rule that would yield such ordered pairs as (-2,-4), (3,6), and (4,8)
- Comparing the properties of two functions represented in different ways (in a table, graph, equation, or description)
- Determining congruence (when shapes are of equal size and shape) and similarity (same shape but different sizes)
- Learning and applying the Pythagorean Theorem (an equation relating the lengths of the sides of a right triangle: a2 + b2 = c2)
- Solving problems involving the volume of cylinders, cones, and spheres
Parent Roadmap - Supporting your child in 8th Grade Mathematics