Sal simplifies a polynomial subtraction expression. [2:07]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Create your own addition/subtraction math facts worksheets. Use them in the classroom for practice or timed drills, or at home! Choose from two levels of difficulty, and vertical or horizontal equation format. You input minimum and maximum values of the numbers to be used, as well as how many questions you'd like, and the site does the rest!

This article provides ideas, lessons and resources on how elementary teachers can integrate map skills, math, and art into lessons about the geography of the Arctic and Antarctica.

On this site from Aussie School House Teachers on the Web, an Australian K-6 teacher defines and illustrates more than 500 mathematical terms. It is a wonderful dictionary featuring clear and often interactive graphics, great colors, and lots of examples. It has been recently updated adding more terms, charts, and an app.

Explains what it means for two triangles to be similar. Diagram of similar triangles is created with two parallel lines cut by two transversals.

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

This is demonstration of how the law of sines works. It uses Java applets to manipulate the triangle and allows the user to explore what happens to the values of the triangle as the sides are changed.

Have you ever seen an item that you wanted on sale for 15% of its original price? Have you tried to figure out what the sale price would be? Using this interactive lesson from T.V. 411, you can learn to calculate discounts with percentages.

Survey says? That is the question today, as students work on three different tasks to assess the how they are doing with the skills from the current unit.

Can you throw a beanbag as far as the Olympic hammer or discus throwers? This activity introduces children to informal measures to compare distances, and is designed to be accessible to primary pupils at Key Stage 1.

Does weight give shot putters an advantage? This activity encourages students to engage in statistical analysis, and is aimed at GCSE and A-level students (Key Stages 4 and 5).

Can you analyse the nutritional needs of a long-distance cyclist to help him plan his calorie intake? This activity provides a real-life context for handling data, converting units and proportional reasoning and is aimed at secondary students at Key Stages 3 and 4.

Four sporty brainteasers in the context of fencing, hockey, football and international medal tables. This activity challenges students to be resourceful, to think logically and to work systematically, and is designed to be accessible to secondary maths students at Key Stages 3 and 4.

This page gives a lot of informaiton on correlation, including a section on the coefficient of correlation.

This resource is the beginning of a series of pages that demonstrates the diffference between the mean and median of a group of numbers. Uses bar graphs to display the data.

This article discusses the Mathematics skills that are essential for a crop farmer, particularly measurement, e.g., time, money, volume, area. The article contains a variety of problems based on real life situations.

This site offers a problem and solution to finding all possible slopes for a line tangent to a circle given a particular equation of a circle. Could be an interesting challenge for students.

Students "go fishing" and use proportions to learn how estimating is used to determine the size of a population.

This lesson describes how to use the quadratic formula to determine the solution of a quadratic equation in a specific format. It is 4 of 16 in the series titled "Using the Quadratic Formula." Includes a short multiple-choice quiz. [2:30]