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Graphic
National Council of Teachers of Mathematics

The Math Forum: Investigating the Golden Ratio

For Students 9th - 10th
This site gives a diagram of a golden rectangle, the value for the golden ratio, and a few problems for students to work relating to the golden ratio. This site does not however explain the significance of this ratio.
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Handout
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Babylonian Number System

For Students 9th - 10th
Dr. Math takes on a question about the Babylonian base-60 math system, explaining how a sexagesimal system looks and works in comparison with our decimal (base 10) system.
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Website
National Council of Teachers of Mathematics

The Math Forum: Seventh Grade Mathematics: Cycles

For Students 6th - 8th
Teachers can use this resource for creating interesting lessons about time and time measurement. There are articles about leap year, converting time, as well as other links for further research. An interdisciplinary project about an...
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Lesson Plan
National Council of Teachers of Mathematics

The Math Forum: Seventh Grade Mathematics: Data Sense

For Teachers 6th - 8th
This site has some interesting ways to collect and evaluate data. There are some activities about note taking, spreadsheets, surveys, and a cool bridge construction project. Teachers may want to use this site as a resource for some...
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Activity
National Council of Teachers of Mathematics

The Math Forum: Seventh Grade Math: Area and Perimeter

For Students 6th - 8th
Learn how to enlarge drawings, figure out how much tile to buy to cover a specific floor, and learn about area and perimeter. These and other lesson plans are provided, including a fun interdisciplinary plan featuring dragons.
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Lesson Plan
National Council of Teachers of Mathematics

The Math Forum: A Tour of Measurement

For Teachers 9th - 10th Standards
Peruse a collection of lesson plans, resources and FAQ's about measurement at every grade level.
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Lesson Plan
National Council of Teachers of Mathematics

The Math Forum: A Collection of Secondary Math Units

For Teachers 9th - 10th Standards
Teachers of grades 9-12 can explore these seven math units for their classes. Data collection and analysis, problem solving with spreadsheets, and linear transformation are just a few of the topics covered here.
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Handout
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Binomial Expansions and Pascal's Triangle

For Students 9th - 10th Standards
This site answers a student's question inquiring about the definition of a binomial expansion, where it would be used, and why.
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Activity
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Formal Definition of a Limit

For Students 9th - 10th
This Math Forum site is an inquiry by a student about the definition of a limit with a response by a professor. If you are confused by the student's inquiry don't worry, take a look at the doctor's response which explains what a limit is...
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Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Two Column Proofs

For Students 9th - 10th Standards
A response to an inquiry of how to prove a two column geometric proof problem at the Math Forum. This site gives a description of what a makes a proof and an example of a two column proof.
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Handout
National Council of Teachers of Mathematics

The Math Forum: Prime Numbers

For Students 9th - 10th Standards
Explains what Prime Numbers are and how to find them. Includes a list of primes under 200 and discusses the Sieve of Eratosthenes. This site has numerous links to other internet sources regarding prime numbers.
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Unit Plan
National Council of Teachers of Mathematics

The Math Forum: Inequalities and Absolute Value Case Method

For Students 9th - 10th
"Dr. Math" responds to a student question on how to use the case method in solving absolute value ienqualities.
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Unit Plan
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Adding and Subtracting Inequaliites

For Students 9th - 10th Standards
"Dr. Math" provides an explanation on remembering when inequalities may be added and subtracted. The explanation is in response to a question submitted by a student.
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Unit Plan
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Interval Notation

For Students 9th - 10th
"Dr. Math" provides an explanation on how to express the solution of a conjunction inequality using interval notation.
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Handout
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Fraction Basics

For Students 9th - 10th
Gives a very basic overview of fractions and their parts. Discusses adding, multiplying, and finding a common denominator.
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Handout
National Council of Teachers of Mathematics

The Math Forum: Why Does 0! = 1?

For Students 9th - 10th
Dr. Math describes the reasoning behind 0! = 1.
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Activity
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Age Word Problems

For Students 9th - 10th
Dr. Math walks you through the necessary steps to solve age problems. Additional examples are included.
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Handout
National Council of Teachers of Mathematics

The Math Forum: The Birthday Problem

For Students 9th - 10th
Dr. Math demonstrates how the birthday problem - what are the odds that two people in a room have the same birthday - works. Several links are available for extended investigations of the problem.
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Activity
National Council of Teachers of Mathematics

The Math Forum: Drexel University: Boy or Girl?

For Students 9th - 10th Standards
Dr. Math explores the probability of the children in families being boys or girls. A look at the mathematics involved in each situation is included.
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Activity
National Council of Teachers of Mathematics

The Math Forum: Geometer's Sketch Pad: An Introductory Lesson

For Students 9th - 10th
This site is a five part tutorial to get started using Geometer's Sketch Pad. The tutorial goes through things such as setting up to install GSP, the tool box, other functions, graphing,and more.
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Activity
National Council of Teachers of Mathematics

The Math Forum: Pi Day

For Teachers 9th - 10th
Need some ideas for Pi Day on March 14th? You can get some great resources at this location. There are all kinds of links available.
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Activity
National Council of Teachers of Mathematics

The Math Forum: Calculation Tips & Tricks: Multiplication Tips

For Students 3rd - 6th
Find tips for multiplying by 5, 9, and 11, and learn how to solve math problems without a calculator. This site includes explanations and examples for gifted children and teachers wanting to challenge their students.
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Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Building Two Column Proofs

For Students 9th - 10th Standards
Use this site to find details of how to construct a two column proof. Dr. Math responds to a question posed by a student and details the reasons for the order of steps and shows two different ways to do the same proof.
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Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Order of a Proof

For Students 9th - 10th Standards
The site gives a diagram of steps to a proof. Dr. Math explains why the step order of a proof is important.