Adding and subtracting integers
4 lessonsAdding signed numbers on the number line, subtraction as adding the opposite, and distance as the absolute value of a difference.
Operations with rational numbers
7 lessonsThe sign rules for products and quotients, all four operations on rational numbers, and decimals that terminate or repeat.
Proportional relationships
9 lessonsA proportional relationship has a constant ratio; recognize it in tables, graphs and equations, and solve proportions.
Percent applications and percent change
12 lessonsThe three percent questions, percent increase and decrease with a multiplier, and money problems from discounts to simple interest.
Equivalent expressions
5 lessonsRewrite linear expressions with rational coefficients by combining like terms, distributing and factoring.
Two-step equations and inequalities
6 lessonsSolve two-step equations and inequalities with rational numbers, including why the inequality sign flips, and use them to solve problems.
Scale drawings
4 lessonsA scale factor multiplies every length; read and make scale drawings, maps and plans, and see what scaling does to area.
Angles, triangles and constructions
8 lessonsComplementary, supplementary, vertical and adjacent angles, and when three lengths make a triangle.
Circles: circumference and area
4 lessonsPi links the diameter of a circle to its circumference, and cutting a circle into slices shows why its area is pi r squared.
Area, surface area and volume of prisms
5 lessonsArea of composite figures, slices of solids, and the surface area and volume of right prisms and cylinders.
Probability
9 lessonsProbability measures chance on a 0 to 1 scale; build probability models and compare them with relative frequencies from experiments.
Compound events and simulation
7 lessonsFind probabilities of compound events with tree diagrams and the counting principle, and estimate them by simulation.
Sampling and comparing populations
9 lessonsRandom samples support inferences about a population, samples vary, and two populations are compared by center and spread.