Linkfest for Friday, May 2

Sometime in the past week, I added mathblogging.org to my feedly feed. They compile posts from all the math blogs they know of, with an interesting mechanism that takes you right to the original blog, instead of just linking to it. Yikes! I was already following hundreds of math blogs, and suddenly my feed doubled or tripled. I'll have to let it go eventually, it's just too much. But I found lots of interesting posts on blogs I'd never seen before, so today's linkfest will be more diverse than usual.

• MAA Minute Math (which has a new problem each weekday) had this problem on Monday: The volume (V), surface area (S), and total edge length (L) for a cube are consecutive terms in an arithmetic sequence. The largest possible side length is a+sqrt b (a,b integers). Find a+b.
• NUM+BER=PLAY, quite a bit harder than the ones that repeat letters/digits.
• 930 impossible figures.
• 37 pounds of garbage (kindergarten math)
• Rebecka's students loved their matrix-encoded scavenger hunt.
• Ashli is reading lots of interesting research. "The policy of requiring a passing score on an Algebra II exam for high school graduation simply cannot be justified."  
• Math for Writers is free for download, today and tomorrow.
• The tides of the quadratic formula. (What can you do with this?)
• Math and quilting, geogebra fun with John Golden.
• The current issue of Nautilus (an amazing online journal) is on symmetry. This issue includes a chapter a week for five weeks. This week's chapter is called 'In Theory', and includes articles on Penrose tiles and fair sharing.
• A primer on Newton's Laws, that starts out by emphasizing how counter-intuitive they are. (Physics, not math, but physics is the reason for calculus, right?)
• Megan Schmidt loved how engaged her students were with Nrich's Digit Doozy problem. I also like their largest product problem. I think I'll put a bunch of their posters up in the math lab in August.
• Bon Crowder says the "summer slide" is a myth. I concur. Let's play with math this summer.
• A puzzle posed as a card game.
• Tantalizing intro to 'The mirror crack'd: why physics is lopsided'. I'd like to read this, but I don't have a subscription. Bummer.
• Graphing game from John Golden.
• Why do math? from Siam, describes how math solves problems. Includes a description of google page rank (though it's not very in-depth).
• A and a half. How an Oregon Trail simulation demonstrates the problems with standardized tests.
• Engaging students in learning the multiplication facts, up to 20 times.

Crazy, how much good stuff there is to read. How can anyone absorb all this?