Looking for free content that’s aligned to your standards? You’ve come to the right place!
Get Free 8th Grade Math Content
Khan Academy is a nonprofit with thousands of free videos, articles, and practice questions for just about every standard.
No ads, no subscriptions – just 100% free, forever.
8.NS The Number System
- 8.NS.A Know that there are numbers that are not rational, and approximate them by rational numbers.
- M.8.NS.A.1 Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and use patterns to rewrite a decimal expansion that repeats into a rational number.
- M.8.NS.A.2 Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line, and estimate the value of expressions (e.g., π2).
- Checkpoint opportunity
8.EE Expressions and Equations
- 8.EE.A Work with radicals and integer exponents.
- M.8.EE.A.1 Know and apply the properties of integer exponents to generate equivalent numerical expressions. For example, 32 x 3-5 = 3-3 = 1/33 = 1/27.
- M.8.EE.A.2 Use square root and cube root symbols to represent solutions to equations of the form x2 = p and x3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that √ 2 is irrational.
- M.8.EE.A.3 Use numbers expressed in the form of a single digit times an integer power of 10 to estimate very large or very small quantities, and to express how many times as much one is than the other.
- M.8.EE.A.4 Use technology to interpret and perform operations with numbers expressed in scientific notation. Choose units of appropriate size for measurements of very large or very small quantities (e.g., use millimeters per year for seafloor spreading).
- Checkpoint opportunity
- 8.EE.B Understand the connections between proportional relationships, lines, and linear equations.
- M.8.EE.B.5 Graph proportional relationships, interpreting the unit rate as the slope of the graph. Compare two different proportional relationships represented in different ways.
- M.8.EE.B.6 Use similar triangles to explain why the slope m is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation y = mx + b for a line intercepting the vertical axis at b.
- Checkpoint opportunity
- 8.EE.C Analyze and solve linear equations and pairs of simultaneous linear equations. (M)
- M.8.EE.C.7 Solve linear equations in one variable.
- M.8.EE.C.7a Give examples of linear equations in one variable with one solution, infinitely many solutions, or no solutions. Show which of these possibilities is the case by successively transforming the given equation into equivalent forms.
- M.8.EE.C.7b Solve linear equations with rational number coefficients, including equations whose solutions require expanding expressions using the distributive property and collecting like terms.
- M.8.EE.C.8 Analyze and solve pairs of simultaneous linear equations.
- M.8.EE.C.8a Understand that solutions to a system of two linear equations in two variables correspond to points of intersection of their graphs, because points of intersection satisfy both equations simultaneously.
- M.8.EE.C.8b Solve systems of two linear equations in two variables by graphing and analyzing tables. Solve simple cases represented in algebraic symbols by inspection.
- M.8.EE.C.8c Solve real-world and mathematical problems leading to two linear equations in two variables.
- Checkpoint opportunity
- M.8.EE.C.7 Solve linear equations in one variable.
8.F Functions
- 8.F.A Define, evaluate, and compare functions.
- M.8.F.A.1 Understand that a function is a rule that assigns to each input exactly one output. The graph of a numerically valued function is the set of ordered pairs consisting of an input and the corresponding output. Function notation is not required in Grade 8.
- M.8.F.A.2 Compare properties of two functions each represented in a different way (algebraically, graphically, numerically in tables, or by verbal descriptions).
- M.8.F.A.3 Interpret the equation y = mx + b as defining a linear function, whose graph is a straight line; give examples of functions that are not linear.
- Checkpoint opportunity
- 8.F.B Use functions to model relationships between quantities. (M)
- M.8.F.B.4 Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values.
- M.8.F.B.5 Describe qualitatively the functional relationship between two quantities by analyzing a graph (e.g., where the function is increasing or decreasing, linear or nonlinear, continuous or discrete). Sketch a graph that exhibits the qualitative features of a function that has been described verbally.
- Checkpoint opportunity
8.G Geometry
- 8.G.A Understand congruence and similarity using physical models, transparencies, or geometry software.
- M.8.G.A.1 Verify experimentally the properties of rotations, reflections, and translations:
- M.8.G.A.1a Lines are taken to lines, and line segments to line segments of the same length.
- M.8.G.A.1b Angles are taken to angles of the same measure.
- M.8.G.A.1c Parallel lines are taken to parallel lines.
- M.8.G.A.2 Understand that a two-dimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations; given two congruent figures, describe a sequence that exhibits the congruence between them.
- M.8.G.A.3 Describe the effect of dilations, translations, rotations, and reflections on two-dimensional figures using coordinates.
- M.8.G.A.4 Understand that a two-dimensional figure is similar to another if the second can be obtained from the first by a sequence of rotations, reflections, translations, and dilations; given two similar two-dimensional figures, describe a sequence that exhibits the similarity between them.
- M.8.G.A.5 Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angle-angle criterion for similarity of triangles.
- Checkpoint opportunity
- M.8.G.A.1 Verify experimentally the properties of rotations, reflections, and translations:
- 8.G.B Understand and apply the Pythagorean Theorem. (M)
- M.8.G.B.6 Justify the relationship between the lengths of the legs and the length of the hypotenuse of a right triangle, and the converse of the Pythagorean theorem.
- M.8.G.B.7 Apply the Pythagorean Theorem to determine unknown side lengths in right triangles in real-world and mathematical problems in two and three dimensions.
- M.8.G.B.8 Apply the Pythagorean Theorem to find the distance between two points in a coordinate system.
- Checkpoint opportunity
- 8.G.C Solve real-world and mathematical problems involving volume of cylinders, cones, and spheres. (M)
- M.8.G.C.9 Know the relationship among the formulas for the volumes of cones, cylinders, and spheres (given the same height and diameter) and use them to solve real-world and mathematical problems.
- Checkpoint opportunity
8.SP Statistics and Probability
- 8.SP.A Investigate patterns of association in bivariate data. (M)
- M.8.SP.A.1 Construct and interpret scatter plots for bivariate measurement data to investigate patterns of association between two quantities. Describe patterns such as clustering, outliers, positive or negative association, linear association, and nonlinear association.
- M.8.SP.A.2 Know that straight lines are widely used to model relationships between two quantitative variables. For scatter plots that suggest a linear association, informally fit a straight line, and informally assess the model fit by judging the closeness of the data points to the line.
- M.8.SP.A.3 Use the equation of a linear model to solve problems in the context of bivariate measurement data, interpreting the slope and intercept.
- M.8.SP.A.4 Understand that patterns of association can also be seen in bivariate categorical data by displaying frequencies and relative frequencies in a two-way table. Construct and interpret a two-way table summarizing data on two categorical variables collected from the same subjects. Use relative frequencies calculated for rows or columns to describe possible association between the two variables.
- Checkpoint opportunity