The following topics are covered in each grade level. 

7th Grade Topics:

Ratios and Proportional Relationships

Rational Numbers

Expressions and Equations

Percent and Proportional Relationships

Statistics and Probability

Geometry

8th Grade Topics:

Real Numbers

Equations in One Variable

Equations in Two Variables

Functions

Triangles and the Pythagorean Theorem

Transformations

Congruence and Similarity

Volume and Surface Area

Scatter Plots and Data Analysis

Algebra Grade Topics:

Polynomials

Introduction to Functions

Solving Linear Functions 

Exponential Functions

Sequences

Radicals

Factoring

Solving Quadratics

Graphing Quadratics

Statistics

Mixed Functions