Here’s a new effort. Links and commentary on math sites, audio/video, books, contests and other resources. Feel free to contribute.
Pine Grove Math Fans, the promised site is up! Click the math ambigram to go there.
Note, the Halton District School Board offers Free Online Mathematics Homework Help, focusing on confidential one-on-one help in mathematics for students in Grades 7, 8, 9 and 10.
Web
WolframAlpha Computational Knowledge Engine, www.wolframalpha.com – Let the fun begin! Calculate just about anything from 1+1 to the time it takes a satellite in a geostable orbit to circle the Earth.
Halton District School Board Free Online Mathematics Homework Help, www.hdsb.ca/StudentResources/Pages/ OnlineMathHomeworkHelp.aspx – Focusing on confidential one-on-one help in mathematics for students in Grades 7, 8, 9 and 10, and available Sunday – Thursday from 5:30 pm to 9:30 pm. Register in class in October, or online at https://homeworkhelp.ilc.org/secure/login.php thereafter. 
KhanAcademy, www.khanacademy.org – “With a library of over 2,700 videos covering everything from arithmetic to physics, finance, and history and 280 practice exercises, we’re on a mission to help you learn what you want, when you want, at your own pace.”
Books
50 Mathematical Ideas You Really Need to Know by Tony Crilly – By exploring the subject through its 50 key insights – from the simple (the number one) and the subtle (the invention of zero) to the sophisticated (proving Fermat’s last theorem) – this book shows how mathematics has changed the way we look at the world around us.
In Code: A Mathematical Journey by Sarah Flannery with David Flannery – Part memoir, part puzzle book, and part mathematical exploration, with scattered bits of mathematical lore. (The heaviest math is concentrated into two chapters and the appendices, leaving the remainder easy going.) 
Secrets of Mental Math: The Mathemagician’s Guide to Lightning Calculation and Amazing Math Tricks by Arthur Benjamin and Michael Shermer – Watch the TED.com video below to see the mathemagician work his art.
Audio/Video
- Conrad Wolfram: Teaching kids real math with computers | Video on TED.com
From rockets to stock markets, many of humanity’s most thrilling creations are powered by math. So why do kids lose interest in it? Conrad Wolfram says the part of math we teach — calculation by hand — isn’t just tedious, it’s mostly irrelevant to real mathematics and the real world. He presents his radical idea: teaching kids math through computer programming. 
A Brief History of Mathematics | Audio on BBC.co.uk – Professor Marcus du Sautoy argues that mathematics is the driving force behind modern science. Ten 15 minute audio podcasts that reveal the personalities behind the calculations from Newton to the present day. - The Story of Maths | Video on TVO.org – Four one-hour episodes shown in January 2010.
- The Story of Maths – The Language of the Universe
- The Story of Maths – The Genius of the East
- The Story of Maths – The Frontiers of Space
- The Story of Maths – To Infinity and Beyond
- Arthur Benjamin does “Mathemagic” | Video on TED.com
In a lively show, mathemagician Arthur Benjamin races a team of calculators to figure out 3-digit squares, solves another massive mental equation … - Scott Kim takes apart the art of puzzles | Video on TED.com Scott Kim designs puzzles in the spirit of MC Escher’s art and Tetris. Demonstrates the relationship between math, art and puzzles. Includes a few minutes on ambigrams.
Contests
- Caribou Math Contest – Brock University: “The Caribou Mathematics Competition is a Canada wide free online contest that is held on six days in a school year, 2011/12 in its fourth year. On each of these days a contest is offered for each of the age groups of grades 3/4, 5/6, and 7/8. Contests are provided in both English and French.”
- CMEC Mathematics and Computing Contests – University of Waterloo: Grades 7 thru 12 and open; prep and past contests with solutions available online.
- Mathematica Centrum – Grades 3 thru 9; prep contest with solutions available online.
