Online Math Library
http://www.mathdl.org/jsp/index.jsp

Practical Algebra Lessons
From purplemath.com, this provides help on a variety of Algebra topics.
http://www.purplemath.com/modules/index.htm

Go Math
This web site includes tutorials on a variety of Algebra I and Algebra II topics, SAT Math Help and Math Games.
http://www.gomath.com/

Algebra Help
This page provides reference help for students in Algebra I or Algebra II
http://www.homeworkspot.com/high/math/algebra.htm

Ask Dr. Math - Algebra
Questions and Answers on a variety of topics in Algebra.
http://mathforum.org/dr.math/tocs/algebra.high.html

Yahoo! Mathematics - http://www.yahoo.com/Science/Mathematics

Yahoo's links to mathematics Web sites giving access to huge number of resources on the Internet. Includes the following subcategories: Academic Papers; Algebra; Applied Mathematics; Ask an Expert; Books; Calculus; Chaos; Combinatorics; Complex Systems; Conferences; Education; Employment; Entropy; Ethnomathematics; Fields Medal; Formal Logic; Fractals; Geometry; History; Humor; Journals; Libraries; Linear Algebra; Mathematical Biology; Mathematicians; Modelling; Number Theory; Numerical Analysis; Operations Research; Organizations; Pre-Algebra; Problems, Puzzles, and Games; Research; Security and Encryption; Set Theory; Software; Statistics; Tools; Wavelets; Web Directories; and Usenet.

About.com - Mathematics - http://math.about.com/science/math/index.htm

About.com's links to mathematics Web sites giving access to huge number of resources on the Internet. Includes the following subjects: Abstract Algebra; Actuarial Math; Algebra; Applied Math; Calculus; Combinatorics; Discrete Math; Geometry; History; How To; Logic; Math Careers; Math Education; Mathematicians; Number Theory; Pre-Algebra; Probability; Analysis; Research Resources; Statistics; Topology; and Tutorials.

Measure 4 Measure: Sites That Do the Work For You - http://www.wolinskyweb.com/measure.htm

Collection of links to web sites that calculate a very large variety of things. Sections include: Science/Math, Health, Finance, and Everything Else.

Mega-Mathematics! - http://www.c3.lanl.gov:80/mega-math/

A project of the lab where the atomic bomb was developed. The MegaMath project is intended to bring unusual and important mathematical ideas to elementary school classrooms so that young people and their teachers can think about them together. (Los Alamos National Laboratory)

The Geometry Center - http://www.geom.umn.edu/welcome.html

Look here for lots of good geometry information. Part of the Center is the Gallery of Interactive Geometry <apps/gallery.html> where you can use your knowledge of geometry to create interesting, artistic images and shapes. Although the Center is no longer maintained links to parts of it are still operational. (U. of Minn.)

The MacTutor History of Mathematics Archive - http://www-history.mcs.st-andrews.ac.uk/history/index.html

This site has information on the entire history of mathematics. Main indexes include: Biographies; History Topics; Famous Curves; and Mathematicians of the Day. The site also has other indexes and a chronology of important dates in mathematics. (School of Mathematics and Statistics, University of St Andrews, Scotland)

Abstract Algebra Online - http://www.math.niu.edu/~beachy/aaol/

"This site contains many of the definitions and theorems from the area of mathematics generally called abstract algebra. It is based on the following books: Abstract Algebra, by John A. Beachy and William D. Blair, and Abstract Algebra II, by John A. Beachy."

HP Calculators - http://www.hp.com/calculators/index.html

The official Hewlett-Packard calculator page, with information about the company's line of calculator products.

Math Art Gallery - http://www-math.sci.kun.nl:80/math/knopen/

See how art can flow out of mathematics. (Catholic University Nijmegen, Netherlands)

The Math Forum - http://forum.swarthmore.edu/

A gathering place for links to Internet information and materials about mathematics. Forum Features include: Search for Math or browse our Internet Mathematics Library; Ask Dr. Math; Discussion Groups; Forum Showcase; Internet Newsletter; Problems of the Week; Teacher2Teacher; and Web Units & Lessons. (Swarthmore College)

Math2.org - http://www.math2.org/index.xml

Formerly called Dave's Math Tables, this Web site includes links for general math, algebra, geometry, trigonometry, odds and ends, statistics, calculus, and advanced topics. In English or Spanish. (David Manura, Scientific Instrument Services)

History of Mathematics - http://aleph0.clarku.edu/~djoyce/mathhist/mathhist.html

Explore the history of math by region, by topic or chronologically. Also has links to books about the subject and organizations devoted to the history of math. One of the features is Euclid's Elements, a Java-enhanced study of Euclid's Geometry and 23 important mathematical problems of David Hilbert. (David E. Joyce, Clark Univ.)

Advanced Calculus and Analysis - http://www.maths.abdn.ac.uk/~igc/tch/ma2001/notes/notes.html

Notes from a college undergraduate course. (Ian Craw, Univ. of Aberdeen)

Ancient Math Documents - http://lcweb.loc.gov/exhibits/vatican/math.html

From the "Rome Reborn" exhibit of the Vatican Library. Documents the effect these ancient texts had on Renaissance culture. Includes facsimiles of documents such as Euclid's Elements, Archimedes' Works, Appolonius' Conics , etc. (Library of Congress)

The Fractory - http://library.thinkquest.org/3288/

"This page will help you learn about fractals: what they are and how to design them, but it will also let you discover more on your own. Fractals are just now emerging as a science. They show an order in seemingly random things, and give us tools with which we can predict the weather, render natural looking objects, and help understand the order in our chaotic lives. You will also play a part in our interactive fractal creation center, designing and  displaying fractals you have invented."

University of Toronto Mathematics Network - http://www.math.toronto.edu/awilk/MathNet/

This is the "new" Web site of the UTMN, which is a group designed to encourage high school students to actively participate in doing mathematics, providing cooperative, competitive, interesting, and interactive projects, as well as more traditional problems and other quality resource material."

University of Minnesota Calculus Initiative - http://www.geom.umn.edu/education/calc-init/

"The Geometry Center is assisting in the development of interactive technology-based modules for the engineering calculus sequence. These modules emphasize geometric concepts of calculus while examining applications of mathematics to the physical and life sciences." Specific projects include the "Rainbow Lab;" "Numerical Integration Lab;" "Beams, Bending, and Boundary Conditions Lab;" and "Modeling Population Growth."

VassarStats - http://faculty.vassar.edu/~lowry/VassarStats.html

"Welcome to the VassarStats web site, which I hope you will find to be a useful and user-friendly tool for performing basic statistical computation. Each of the links" ... (Probabilities; Distributions; Frequency data; Proportions; Ordinal data; Correlation & regression; t-Tests & procedures; ANOVA; ANCOVA; and Miscellanea) "will show an annotated list of the statistical procedures available under that rubric. Some of these procedures will be launched in a new browser window. In this case, simply close the new window to return to the main page."

Geometry in Action - http://www.ics.uci.edu/~eppstein/geom.html

"This page collects various areas in which ideas from discrete and computational geometry (meaning mainly low-dimensional Euclidean geometry) meet some real world applications. It contains brief descriptions of those applications and the geometric questions arising from them, as well as pointers to web pages on the applications themselves and on their geometric connections. This is largely organized by application but some major general techniques are also listed as topics.

Geometry.Net - http://www.geometry.net/

A website all about geometry. Links are provided for such topics as: Basic Math: Geometry, Algebra, Calculus...; Biographers [sic]: Euclid, Boole, Goedel...; Pure and Applied Math: Logic, Topology, Category...; Physics: Atomic Physics, Electronics...; Computer & Internet: C++, Java, HTML...; Biology: Genetics, Biochemistry...; Technology: Architecture, Biotechnology...; and Sports: Basketball, Baseball, Football... Other links are given for Categorical Geometry; Site Map links; Math Help Desk; Calculus Learning; Famous Theorems; Math Discover; Test Prep Central; Computer_Certification; New Math Books; and Mathematicians.

The Zero Saga & Confusions with Numbers - http://ubmail.ubalt.edu/~harsham/zero/ZERO.HTM

This site explains the history, value of the concept, and symbol of zero, and its role in mathematics. From a professor at the University of Baltimore.

Biographies

Mathematicians of the 17th and 18th Centuries - http://www.maths.tcd.ie/pub/HistMath/People/RBallHist.html

Mathematicians of the seventeenth and first half of the eighteenth century, adapted from A Short Account of the History of Mathematics by W. W. Rouse Ball (4th ed., 1908). These biographies constitute part of the collection of online material relating to the history of mathematics. (School of Mathematics, Trinity College, Dublin)

Biographies of Women Mathematicians - http://www.agnesscott.edu/lriddle/women/women.htm

These pages are part of an on-going project by mathematics students to illustrate the numerous achievements of women in the field of mathematics. (Agnes Scott College, Atlanta, GA)

MacTutor History of Mathematics Archive - http://www-groups.dcs.st-and.ac.uk:80/~history/

This archive contains the biographies of more than 1000 mathematicians. About 200 of these biographies are fairly detailed and most are accompanied by pictures of the mathematicians themselves. (School of Mathematics and Statistics, Univ. of St. Andrews, Scotland)

Mathographies - http://scidiv.bcc.ctc.edu/Math/MathFolks.html

Bibliographies of mathematicians, provided by a community math faculty. Includes approximately 30 biographies in a time period from ancient to modern. (Bellevue Community College)

Mathematician Biography Index - http://www-groups.dcs.st-and.ac.uk/~history/BiogIndex.html

Features brief biographies for most important mathematicians in history.

Mathematicians (Google Directory) - http://directory.google.com/Top/Kids_and_Teens/School_Time/Math/Mathematicians/

Annotated links to sites about mathematicians. Several mathematicians, including Archimedes, Benjamin Banneker,  Rene Descartes, Albert Einstein, Euclid, Hypatia, Isaac Newton, Blaise Pascal, and Pythagoras, have several sites dedicated to them.

Mathematical Tourist

Four Color Theorem - http://www.cs.uidaho.edu/~casey931/mega-math/gloss/math/4ct.html

Short explanation of the famous theorem about the number of colors it takes to show distinct areas on a map.

The Four Color Theorem - http://www.math.gatech.edu/~thomas/FC/fourcolor.html

"This page gives a brief summary of a new proof of the Four Color Theorem and a four-coloring algorithm found by Neil Robertson, Daniel P. Sanders , Paul Seymour and Robin Thomas." (Georgia Tech)

The Four Colour Theorem - http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/The_four_colour_theorem.html

This page gives a history of the theorem with links to other sites about the problem, including the one listed just above. (MacTutor History of Mathematics archive)

The Journey of the Four Colour Theorem Through Time - http://matholymp.com/ARTICLES/4color.pdf

An 11 page article in PDF format which surveys the history of the theorem and discusses the philosophical implications of its recent computer-aided proof. (Andreea S. Calude, Univ. of Auckland)

The Prime Pages - http://www.utm.edu/research/primes/

This is a page all about prime numbers. Links include: The largest known primes; Prime links; Lists of primes; Finding primes & proving primality; and The largest known prime by year: a brief history. (Chris Caldwell, Univ. of Tenn. Martin)

Conic Sections

Conic Sections - http://thorin.adnc.com/~topquark/math/conicsec.html

"This applet allows you to specify a plane in three-dimensional space. The applet plots the intersection of the plane with a cone whose sides have unit slope. When in range, the intercepts of the plane are indicated by blue dots on the axes."

7 Conics -

excerpted from the 30th Edition of the CRC Standard Mathematical Tables and Formulas.

Dave's Math Tables: Conic Sections -

illustrations and sample problems.

ExploreMath.com: Conic Sections -

multimedia presentation allowing one to experiment with parabola, ellipse, and hyperbola problems.

Geometric Concepts for Curves in 3D -

offers an introduction to focal conics.

Instructional Unit on Conic Sections -

tutorial by June Jones.

Introduction to Conic Sections -

examples, exercises, and history.

MathWorld: Conic Section -

offers examples of the nondegenerate curves generated by the intersections of a plane with one or two nappes of a cone.

SparkNotes: Conic Sections -

offers an introduction to, and example problems relating to, the two-dimensional figure created by the intersection of a plane and a right circular cone.

Special Plane Curves: Conic Sections -

mathematical illustrations and links to other resources.