Purple Math
Purplemath: "Work" Word Problems
Explains the "trick" to "work" word problems (such as two people painting a room, or two pipes filling a tank), and demonstrates how to set up and solve these exercises.
Purple Math
Purplemath: Basic "Percent Of" Word Problems
Demonstrates how to set up and solve 'percent of' word problems such as 'What percent of 16 is 5?'.
National Council of Teachers of Mathematics
The Math Forum: Famous Problems in the History of Mathematics
On this site, there are several math problems to explore and solve. Look through some solutions by famous mathematicians and expand your thinking about some interesting math concepts. Teachers of elementary grades may want to use this...
Wolfram Research
Wolfram Math World: World's Most Extensive Mathematics Resource
MathWorld provides a huge mathematics encyclopedia detailing the concepts of geometry, algebra, calculus, discrete math, number theory, and other math topics--complete with formulas, diagrams, examples, and references for thorough...
Math Medics
S.o.s. Math: Math Review Resources
A math tutorial for many areas of math that contains over 2,500 pages of explanations and examples in algebra, trigonometry, calculus, and basic mathematics. Also has exams and ask-an-expert function.
Other
Problems in the Points Contest of Ko Mal
Learn about the annual KoMal competition in mathematics, physics, and information technology, and challenge your ability to solve problems involving advanced algebra, logic, and other related topics through the tests provided at this site.
Math Playground
Math Playground: Problem Solving Videos
"Rated 'M' for middle school," Math TV invites you to tune in each week for videos of word problems being solved. Back episodes are available in subjects such as percentages, number sense, and fractions. Watch a problem worked out, then...
Ducksters
Ducksters: Kids Math: Solving Algebra Equations With Addition and Subtraction
Kids learn about Solving Algebra Equations with Addition and Subtraction. Add and subtract from both sides. Example math problems are shown on page.
Ducksters
Ducksters: Kids Math: Solving Algebra Equations With Multiplication and Division
Kids learn about Solving Algebra Equations with Multiplication and Division. Multiply or divide from both sides. Example math problems are found on the site.