This article includes the URL and description of 100 free web tools that can be used by all teachers. The tools are categorized into search engines, math and science, games, templates and lesson plans, and more.

This game helps you practice adding tens. You will get to see a percent score of the answers you have correct, as well as running totals of the answers you have correct and incorrect.

This lesson is about counting by tens from AAAmath.com. There are separate sections for learning, practice, playing a game, and exploring more about skip counting.

Equating an integer with a whole number for these purposes, this lesson explains how to multiply fractions by an integer. Provides problems and games to work on this skill.

Through this tutorial you can learn about ordinal numbers, practice using them, and play some games where you use your new information.

This lesson contains a learning exercise in which the user has to find the greatest common factor and type it in. The exercise keeps track of how many right and wrong answers given and gives you a grade.

Practice solving addition and subtraction problems with integers (positive and negative numbers). Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

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.

Twin studies track how similar identical and fraternal twins are on various characteristics, even if they don't grow up together. Correlation lets researchers put a number on it. Scroll down the page to find comprehensive student and teacher guides to accompany the video. [10:50]

This lesson will show you how to use the proper formula and rewrite an equation as a logarithm and then again as an expression with an exponent. It is 8 of 10 in the series titled "Exponential to Logarithmic Format." [2:59]

In this lesson, students learn about additive inverses and absolute values.

A free CK-12 account is required to view all materials.

Video solving a radical equation that results in a quadratic equation and yields an extraneous solution. Explains how the extraneous solution appeared. [11:10]

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.

Learn how to factor quadratic expressions. Includes examples, videos, review exercises, and a quiz.

A free CK-12 account is required to view all materials.

This video demonstrates how to graph a linear equation by creating a table of x, y values to use as coordinates for the graph of the line. The second example demonstrates how to take a word problem and create a table of values to graph in order to show the linear relationship applied in the problem. The last sample problem shows how to interpret a linear graph in order to determine specified values. [13:09]

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.

Explore how to determine the amount of compound interest earned on an investment. Assess learning with a quiz. [4:56]

Real world examples are used to show exponential functions in this lesson. Assess learning with a quiz. [2:18]

This lesson will provide real world examples that involve graphing exponential functions. It is 5 of 5 in the series titled "Exponential Functions in the Real World." [3:09]

Solve linear systems using multiplication.

A free CK-12 account is required to view all materials.

In this lesson students graph ordered pairs in the four quadrants of the coordinate plane. Students examine guided notes, review guided practice, watch instructional videos and attempt practice problems.

A free CK-12 account is required to view all materials.