http://mathforum.org/yeargame/2010/

Write expressions for each of the counting numbers 1 through 100, using the digits in the year 2010, standard operations, and grouping symbols. You may use the digits in any order, but the order 2, 0, 1, 0 is preferred. This year we will also allow the use of decimal points and double-digit numbers. This puzzle is appropriate for students in grades 3-12 with a general knowledge of mathematics.

Students may use the Web form to submit solutions starting January 1, 2010; revisit the site after February 1, 2010, to see the first solutions.

Pages available for printing:

Worksheet

http://mathforum.org/yeargame/2010/2010.worksheet.html

Rules of the Game

http://mathforum.org/yeargame/2010/2010.rules.html

Manipulative Worksheet

http://mathforum.org/yeargame/2010/2010.manipulative.html

http://www.keypress.com/gsp

The Geometer's Sketchpad® is a dynamic construction, demonstration, and exploration tool that adds a powerful dimension to the study of mathematics. You and your students can use this software program to build and investigate mathematical models, objects, figures, diagrams, and graphs.

Beyond innovations in performance and usability, such as video game-quality graphics and advanced data handling, Sketchpad 5 offers:

• Transformable Pictures
• Hot Text™
• Marker Tool
• Expanded Algebraic Capabilities
• Expanded Geometric Capabilities
• Improved Display
• Integrated Support and Curriculum

See a full list of features on the site above, as well as introductory videos and classroom materials.

You can download the software for free, but until you get an authorization code it's limited to 20 minutes at a time, and cannot save, copy, or print. There is a charge for upgrading from an earlier version; see the web page above for details.

geometry.software.dynamic

http://mathforum.org/kb/forum.jspa?forumID=131

You'll find Scott Steketee, former math and computer science teacher and current member of the Sketchpad team, posting on the dynamic geometry discussion, hosted by the Math Forum. This is a discussion of such geometry software programs as the Geometer's Sketchpad and Cabri Geometry II. This group talks about ways of teaching using this technology and the behavior of these programs in specific situations, and sometimes shares sketches.

Registration is free.

http://www.tricki.org/

The Tricki is a wiki "repository of mathematical know-how" that encompasses techniques ranging from the very general to those that concern particular subareas of mathematics.

Browse problem-solving ideas by technique:

• finding algorithms and algorithmic proofs
• approximating one thing by another
• classifying mathematical structures
• comparing sets and mathematical structures
• counting
• solving equations
• obtaining estimates
• proving existence
• producing explicit examples
• proving equalities and identities
• proving impossibility and nonexistence
• proving inequalities
• maximizing and minimizing
• proving "for all" statements

You can also search, browse by mathematical subject area, and read general problem-solving tips and information on how to use these mathematical concepts and statements.