Oregon Department of Education
Building Number Sense
It's never too early to begin a child's math education. This collection of fun hands-on activities engage youngsters in building their number sense as they learn how to count objects, identify numerals, compare amounts, and much more.
Lawrence Hall of Science
The Math Page: Skill in Algebra: Adding Algebraic Fractions
Here is a site that clearly and thoroughly explains adding algebraic fractions (rational expressions) both with common denominators and with different denominators. There are example problems solved, problems for the student to attempt,...
Oswego City School District
Regents Exam Prep Center: Adding and Subtracting Fractions
Use this site to learn how to add and subtract algebraic fractions, even if there aren't common denominators. Provides plenty of examples.
Help Algebra
Help algebra.com: Simplifying Rational Expressions
The process of factoring and canceling is used to simplify, multiply, and divide rational expressions. Adding and subtracting rational expressions is also demonstrated, including finding common denominators.
Math Medics
S.o.s. Math: Complex Fractions/rules for Operations
A brief look at multiplying, adding, and subtracting complex fractions with links to rules.
Interactive Mathematics
Interactive Mathematics: Addition & Subtraction of Fractions
The addition and subtraction of algebraic expressions is presented with detailed examples and exercises for extra practice.
Interactive Mathematics
Interactive Mathematics: Factoring and Fractions
Polynomials are the focus of these lessons, concentrating on factoring and special products to work with rational expressions. Interactive tools of Live Math and Scientific Notebook are used to provide animated solutions to the examples....
Math Is Fun
Math Is Fun: Using Rational Numbers
This site offers simple examples for adding, subtracting, multiplying, and dividing rational numbers. It also provides examples of writing fractions in simplest form and as mixed numbers or improper fractions. Students can test their...