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  All Sites - 394 items found, showing 51 to 100

  1. Discovering Polygons and Polyhedra - Paul Scott; applets by Bob Allanson
    To encourage exploration of polygons and polyhedra in an interactive way, and to appreciate their beauty. The site contains many diagrams and applets, and invites readers to explore and find answers for themselves. ...more>>

  2. Dissections: Plane & Fancy - Greg Frederickson, Cambridge University Press
    A book that explores an area of mathematical recreations, called geometric dissections, or the cutting of one or more figures into pieces that can be rearranged to form other figures. With an emphasis on using as few pieces as possible, these geometrical ...more>>

  3. Dissection (The Geometry Junkyard) - David Eppstein, Theory Group, ICS, UC Irvine
    An extensive annotated list of links to material on problems of cutting a region (such as a polygon into the plane) into pieces (possibly putting them together to form a different polygon). Related topics include tiling (in which the whole plane is cut ...more>>

  4. DLK MathsWork Software
    Self-differentiating, topic-specific math software for Windows 3.1 and above, on number, shape and space, and data handling. All of the practice modules have on screen monitoring at three levels. Six problem modules designed to improve users' application ...more>>

  5. Dominoes Activity - Suzanne Alejandre
    A classroom activity (similar to Pentomino + 1 = Hexomino; a variation on polyominoes) aligned to the NCTM and California Standards, to be explored through manipulatives (paper dominoes). Students explore whether it is possible to cover a 6x5 grid with ...more>>

  6. Don Hatch's Home Page - Don Hatch
    Hyperbolic tessellations shown in various stages of truncation, and represented by their Schlafli symbols. Java applets explore hyperbolic tessellations, a magic Rubik's-like cube in four dimensions, polygon reciprocation (dual), modern portfolio theory ...more>>

  7. Doodling and Miracles - Cut the Knot!, Alexander Bogomolny
    Almost 100 years ago, Frank Morley proved a curious theorem from elementary geometry that had remained unknown until 1899. With time, the theorem became known in mathematical folklore as Morley's Miracle (Morley's Trisector Theorem is a more mundane term.) ...more>>

  8. Drums That Sound Alike - Ivars Peterson (MathLand)
    Peterson writes that physicists and mathematicians have long recognized that the shape of the boundary enclosing a membrane plays a crucial role in determining the membrane's spectrum of normal-mode vibrations. He outlines the progress made on Mark Kac's ...more>>

  9. Educational Videos and Software for K-12 - Allied Video Corporation
    Educational videos, software, and Web page services. The math series includes The Assistant Professor math videos (Fractions and All Their Parts; All About Angles; What is Area?; What are Variables?; The Pythagorean Theorem; Which Way is Minus?; The World ...more>>

  10. Edutest: Online Assessment Resource
    Assessment testing based on nationally recognized standards in Math and Language Arts for grades 2-8. Scoring is instant and both parents and teachers can review the tests and the correct answers with their students. The site has some information for ...more>>

  11. Eighth Grade (AAA Math) - John Banfill
    Interactive math exercises, lessons, and games covering basic arithmetic concepts and methods, for eighth grade. ...more>>

  12. Erich's Packing Center - Erich Friedman
    A huge collection of packing problems, each explained with graphics. 2D examples include Triangles in Squares, Circles in Squares, Squares in Squares, Triangles in Triangles, Circles in Triangles, Squares in Triangles, Triangles in Circles, Circles in ...more>>

  13. Essay Ideas - Jim Wilson, Dept. of Mathematics Education, Univ. of Georgia
    For a course on Using Computers in Mathematics Instruction. Friday the 13th (show there are at most three and at least one Friday the 13th in each year, consider when two consecutive months can be have Friday the 13th); Gingerbread Man (a Microsoft Excel ...more>>

  14. The Euler Line and the 9-point Circle - Interactive Mathematics Miscellany and Puzzles, Alexander Bogomolny
    A geometric explanation of the Euler Line - how complex numbers give us a broader outlook on the geometric configuration - and the 9-point circle of a triangle ABC, which passes through the feet of the three altitudes, the midside points of ABC, and the ...more>>

  15. The Euler Line of a Triangle - David Joyce; Dept. of Mathematics & Computer Science, Clark University
    A draggable geometry applet illustrating the centroid, circumcircle and circumcenter, and altitudes and orthocenter of a triangle, and the straight line they all lie on, the Euler line. ...more>>

  16. The Event Inventor - Kye Ewing
    Science, math, and technology explorations with no experience necessary. (Explorations can often be done by older children with no help.) Make your own quadrant and cross staff and explore the world around you - measuring heights of buildings or trees ...more>>

  17. Examples of Essays - Jim Wilson; Dept. of Mathematics Education, Univ. of Georgia
    Extended Concurrencies of the Triangle, J. Wilson; Parabolas Inscribed in a Triangle, G. Giddings; Polygonal Spirals, L. Shook and M. Callinan; Roots 2 and 5, J. Wilson; Those Amazing Palindromes, Shareef Bacchus; Tangrams, Greg Huberty; Phi: That Golden ...more>>

  18. Exercises in Math Readiness for University (EMR) - Dept. of Mathematics and Statistics, University of Saskatchewan
    A collection of exercises with solutions/tutorials for high school mathematics topics important for university study in mathematics, sciences, engineering and commerce. Exercises at three degrees of difficulty, covering graphing, solving inequalities, ...more>>

  19. Explorations of a Problem with Two Squares - Jim Wilson; Dept. of Mathematics Education, Univ. of Georgia
    Given a square of side s and segments drawn from each vertex to the midpoint of the second side, counting counter-clockwise, the segments intersect to form a new square. What is the ratio of the area of the shaded square to the area of the original square? ...more>>

  20. ExploreMath.com - Third Millennium Press
    Shockwave activities illustrating real-time correlations between equations and graphs to help students visualize and experiment with concepts from elementary algebra through pre-calculus: experiment with the graphs of functions, systems, and complex numbers. ...more>>

  21. Extended Concurrencies of a Triangle - Jim Wilson; Dept. of Mathematics Education, Univ. of Georgia
    An exploration: take any triangle ABC. Construct equilateral triangles externally on each side and locate the center of each equilateral triangle. Label these centers A', B', and C' for the triangle centers opposite angles A, B, and C. Construct lines ...more>>

  22. Eye Opener Series - Interactive Mathematics Miscellany and Puzzles, Alexander Bogomolny
    A collection of Java applets that illustrate and thus help to solve or prove various math problems: Euclid's Proof of the Pythagorean Theorem; Construction problem; Disappearing Lines puzzle; Sam Loyd's fifteen; Sliders puzzle; Lucky 7 puzzle; Happy 8 ...more>>

  23. Faceted Objects: Tanks to Teapots - Paul Flavin
    A "Tiny Library of Faceted Surfaces." Cube, Venus de Milo Statue, Utah Teapot, M-1 Tank, Ludwig Beethoven, magna Girl. For each object the format, number of vertices, number of facets, geometry (shape), bytes, and filename are listed. ...more>>

  24. Fagnano's Problem - Interactive Mathematics Miscellany and Puzzles, Alexander Bogomolny
    An interactive discussion of H. A. Schwarz's and L. Fejér's solutions to Fagnano's problem: inscribe in a given acute-angle triangle the triangle of a minimum perimeter. ...more>>

  25. The Fibonacci Numbers, Pineapples, Sunflowers, and the Golden Mean - Don Cohen (The Mathman)
    Mathematics from a Pineapple: Infinite sequences, limit of a sequence, ratios, fractions, and decimals. Also Looking at a Regular Pentagon. Sample problems with some answers from Chapter 7 of Don Cohen's worksheet book. ...more>>

  26. Figures and polygons - Mark Motyka, Math League Multimedia
    Definitions and illustrations: Polygon; Regular polygon; Vertex; Triangle; Equilateral triangle; Isosceles triangle; Scalene triangle; Acute triangle; Obtuse triangle; Right triangle; Quadrilateral; Rectangle; Square; Parallelogram; Rhombus; Trapezoid; ...more>>

  27. Finding the Smallest Triangle - Jim Parks
    A script for finding the triangle of minimum perimeter inscribed in a given triangle. ...more>>

  28. Finding the Sum of the Exterior and Interior Angles of a Polygon (SMILE) - David Drymiller, Morgan Park High School
    A geometry lesson designed to teach students to find the sum of the interior angles and the sum of the exterior angles of any polygon; review linear measurement to the nearest sixteenth of an inch and angle measurement to the nearest degree; and construct ...more>>

  29. First Curriculum - Patricia Simis Lundy
    A first grade early literacy curriculum. In the Discovery Zone introduces the scientific method; Weather or Not uses grids, mapping, measurement, and number sense; see Our Big Backyard, showing the integration in the various lessons of literature and ...more>>

  30. Flash Demos for Understanding Statistics - G. Donald Allen, Texas A&M University
    Dynamic demonstrations to help foster an understanding of the graphing and variance for data sets. Create a histogram and show the variance; show the mean, variance, and correlation of self-selected data points; understand variance by creating data sets; ...more>>

  31. Flash Games - ATK Solutions, Inc.
    Flash applets and games include rotating 3d cube; mind boggle square, which challenges you to slide a square across a surface by sliding other quadrilaterals into the unoccupied spaces; Futoshiki, which involves positioning counting numbers on a grid ...more>>

  32. Flexagon - Magnus Enarsson
    "A flexagon is a polygon folded from paper with a very remarkable quality: you can turn it inside out to make it reveal hidden surfaces." History, including the original discovery of the tri-hexaflexagon by Arthur H. Stone, as he folded strips of paper ...more>>

  33. Flexagon Re'flex'ions
    Several possibly new trihexaflexagon phenomena are presented, with a wide spectrum of findings including explorations with magic squares, palindromes, and much more. ...more>>

  34. Flexagons - Conrad, Hartline
    Introduction: The story of the Flexagon; Building and Operating the Flexagon; The Covering Space Representation of Flexagon Operation. ...more>>

  35. Folding Maps - Ivars Peterson (MathTrek)
    Erik D. Demaine of the computer science department at the University of Waterloo in Ontario and his coworkers have developed an efficient method for recognizing when a creased sheet is foldable into a flat package (results are reported in an unpublished ...more>>

  36. Formula Determination (SMILE) - Clark Odom, Collins High School
    A lesson designed to teach students to determine the number of degrees in any convex polygon. From the Patterns and Logic section of a collection of almost 200 single concept lessons by the Science and Mathematics Initiative for Learning Enhancement. ...more>>

  37. Forum Geometricorum - Paul Yiu, Editor; Department of Mathematical Sciences, Florida Atlantic University
    A journal on classical Euclidean geometry and related areas. The goal is to bring to a wide, international readership the beauty, elegance, and usefulness of elementary geometry, in research and in teaching. The journal focuses on concrete but challenging ...more>>

  38. Four Construction Problems - Cut the Knot!, Alexander Bogomolny
    Construct a triangle, given the three points in the plane that are the outer vertices of equilateral triangles constructed outward on the sides of the desired triangle. Construct a triangle, given the three points in the plane that are the centers of ...more>>

  39. Four Numerical Triangles in Nexus - Len Smiley
    Three well-known combinatorial number triangles are tightly related to each other as coefficients in transforms of a seminal sequence of exponential generating functions (for n^{n+m}). A fourth triangle is a part of the picture in much the same way that ...more>>

  40. Fractiles-7 - Max Pelletier, Beverly Johnson
    Magnetic tiles that use angles based on the number 7 and allow you to make designs with repeating and non-repeating patterns. Create starbursts, spirals, butterflies, mandalas, flowers, spaceships, and more. Offers a good way to introduce tiling theory ...more>>

  41. Fractions, Simplifying Parts of Shapes: 1/2, 1/3, 1/4 (SMILE) - Sarah Austin, Mary Bethune School
    A lesson designed to teach students that parts are equal to their counterparts; that combined parts equal a whole; that any shape can be divided equally into parts; and to draw shapes, separate them into equal parts and write them in fractional form. ...more>>

  42. Frequently Asked Questions About Trigonometry - J. David Eisenberg
    An interactive site that explains the ideas behind trigonometry. With Java applets for experimenting with triangles and audio files for hearing the pronunciation of trigonometric terms. ...more>>

  43. From Lewis Carroll to Archimedes - Cut the Knot!, Alexander Bogomolny
    On March 29, 1879, Vanity Fair began offering its subscribers a new weekly puzzle invented by Lewis Carroll... on March 17, 1953 Frank Gray, a research scientist at Bell Labs, filed patent no. 2632058, for the Gray code encoding the vacuum tube. An n-digit ...more>>

  44. FUNdamentally MATH - Chip Publications
    A commercial DOS/Windows program covering kindergarten through grade 12 math topics (Basic skills: Addition, subtraction, multiplication, division, negative numbers; Fractions: ordinary and decimal; Middle school geometry; Exponents: powers, roots, number ...more>>

  45. The FUNKtion - Appreciating Math through Art - ThinkQuest 1996
    How to do really hard graphic stuff. Tilings, Fractals, Sierpinski Gaskets, animations, pictures, links. Math "crash courses" on Complex Numbers; Magnitude and the Pythagorean Theorum; Functions; and 3-D. ...more>>

  46. Gary Haynes - Gary Haynes
    Course syllabi, lesson plans, homework, and objectives. Visit "Tangrams and Other Games" for an interactive tangram story and a Flash presentation on how to develop an understanding of functions through the use of the motion sensor. ...more>>

  47. Gecko Stone - John August
    Tessellated, interlocking concrete pavers and molds. Like Escher's reptile, the tessellating shapes are modified hexagons. ...more>>

  48. GED Math Graphics - Howard Myers
    Graphical GED test preparation designed for addiction treatment nonprofits, domestic violence shelters, community based organizations, and other, traditionally resource-constrained programs attended by disadvantaged or indigent students. ...more>>

  49. Geometiles - Yana Mohanty
    Interlocking tiles for exploring plane and three-dimensional geometry, among other math topics. Purchase provides access to a variety of workbooks. Blog posts by creator Mohanty, an electrical engineer who earned a PhD in mathematics before teaching college ...more>>

  50. Geom-e-Tree - John Miller
    Explore fractals with this tree-drawing app for iPod, iPhone, and iPad. Choose the number of branches, angle between branches, and the common ratio of the levels in the tree. See, in particular, the exercises and open questions on Geom-e-Tree for the ...more>>

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