Curated OER
Order in the Classroom
First graders define and identify integers, rational, irrational, real, and complex numbers. They place number cards in ascending and descending order.
Wolfram Research
Wolfram Math World: Rational Number
This site gives an overview of rational numbers, gives interesting facts about the rational numbers including countability and probability of a rational numbers denominator being even. The site also contains related links.
![Inside Mathematics: Picking Fractions [Pdf] Lesson Plan](https://d15y2dacu3jp90.cloudfront.net/images/attachment_defaults/resource/large/FPO-knovation.png "Inside Mathematics: Picking Fractions [Pdf] Lesson Plan")
University of Texas
Inside Mathematics: Picking Fractions [Pdf]
This task challenges a student to demonstrate understanding of the concept of equivalent fractions.
University of Saskatchewan (Canada)
University of Saskatchewan: Decimal Expansions
The University of Saskatchewan's Department of Mathematics and Statistics provides high school students with an online tutorial on decimal expansions. It begins with a focus on decimal representation of real numbers, followed by how this...
Cut the Knot
What's a Rational Number?
This question is answered by discussing and comparing rational and irrational numbers. For more advanced levels of Algebra, there are sections that discuss different lemmas of rational numbers and give their proofs.
Math.com
Math.com: The Language of Algebra: Definitions
The resource investigates the algebra vocabulary. Detailed definitions, examples, and practice problems are included.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Numbers
Math Forum response to request for information on various number sets. Also defined and discussed are integers, natural numbers, whole numbers, irrational numbers, transcendental numbers, and algebraic numbers.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Rationalizing the Denominator
Site gives an explaination on why we rationalize the denominator.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Rational Numbers and Square Ro
Math Forum response to which numbers, other than squared positive integers, can be simplified as rational numbers.
PBS
Pbs Learning Media: Importance of the Origin
The CyberSquad tries to rescue the Cyberchase Council, which is being held captive by Hacker in this video segment from Cyberchase.
TED Talks
Ted: Ted Ed: A Brief History of Numerical Systems
1, 2, 3, 4, 5, 6, 7, 8, 9 and 0. With just these ten symbols, we can write any rational number imaginable. But why these particular symbols? Why ten of them? And why do we arrange them the way we do? Alessandra King gives a brief history...
CK-12 Foundation
Ck 12: Algebra: Properties of Rational Numbers
[Free Registration/Login may be required to access all resource tools.] Recognize and identify irrational numbers and the set of real numbers
CK-12 Foundation
Ck 12: Arithmetic: Conversion of Decimals, Fractions, and Percent
[Free Registration/Login may be required to access all resource tools.] Understand, identify and find equivalent forms of rational numbers
CK-12 Foundation
Ck 12: Arithmetic: Comparison of Rational Numbers
[Free Registration/Login may be required to access all resource tools.] Compare and order rational numbers on a number line and by using inequality symbols
CK-12 Foundation
Ck 12: Algebra: Irrational Square Roots
[Free Registration/Login may be required to access all resource tools.] Find approximate solutions to equations involving irrational numbers.
CK-12 Foundation
Ck 12: Algebra: Equations With Decimals, Fractions, and Parentheses
[Free Registration/Login may be required to access all resource tools.] Solve multi-step equations that involve rational numbers
University of Utah
University of Utah: Rational Number Tutorial
Use this site to learn the basics about rational numbers in this tutorial. There are exercises to check for understanding are included.
University of Vienna (Austria)
University of Vienna: Number Sets
Interactive assessment (with multiple correct answers) which determines depth of knowledge in rational, natural, and integer numbers.
CK-12 Foundation
Ck 12: Arithmetic: Order of Real Numbers Grade 8
[Free Registration/Login may be required to access all resource tools.] Learn how to classify, order, and graph real numbers.
CK-12 Foundation
Ck 12: Algebra: Sets and Symbols
[Free Registration/Login may be required to access all resource tools.] Classify real numbers as rational numbers, whole numbers, integers, and irrational numbers.
Quia
Ixl Learning: Irrational Numbers
Brush up on your math skills relating to irrational numbers then try some practice problems to test your understanding.
Better Lesson
Better Lesson: Rational Numbers on the Number Line Stations
The number line is a useful tool to use when ordering rational numbers.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Irrational Powers
Math Forum response considering whether an irrational number taken to an irrational power yields a rational or irrational number. Responses include a method of generating irrational #s x & y such that x^y is rational.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Rational and Irrational Number
Math Forum response to the size of the set of rational numbers. Responses investigate the countability of sets and basic set theory.