Month: April 2012

Total 13 Posts

Five Favorites — 101Questions [4/28/12]

  • Locked iPad, Jeff. I love that math makes large, incomprehensible numbers a little more comprehensible. How many days, weeks, or years will I have to wait to try another passcode?
  • Bake House Piano Drop 2012, Jeffrey Kirby. They really only had one shot at this. No do-overs. So how did they calculate the position of the ground piano for impact with the flying piano?
  • When you wish upon a star …, Statler Hilton. I want to see what this looked like from the air. This had to be carefully laid-out and diagrammed.
  • Giant Domino, Ian Frame. A gaggle of these popped up after my NCTM talk yesterday (during which I plugged 101questions). These enormous objects litter a small acreage surrounding the Philadelphia convention center, inspiring a pile of interesting questions related to scale. “How tall is the person who is playing with this domino?” will get you first-order similarity. “How heavy is he?” gets you the third order.
  • File Cabinet – Act 1, Andrew Stadel. Crazy bananas. Thankfully, only one of us has to do this for all of us to use it and, lucky for him, he only has to do it once.

Also interesting:

  • Floor 13 please, Luke Walsh. I had a back-and-forth with Karim Ani over this first act. As of this writing, all four of Luke Walsh’s “students” want to know how heavy the average person is. Meanwhile, Walsh asks his students, “What is the area in square feet of this elevator?” That difference interests me. It seems, perhaps, typical of the student-teacher relationship where I can always override my students’ preference by the power vested in me as a teacher, a grown-up, and a person who is several feet taller than they are. All other characteristics of a task being equal, though, I’d rather its question be something that occurs naturally to them or that seems natural when I pose it. 101questions helps me locate those natural-seeming questions.

Plus my own listing:

  • Portal Laser. I uh got kinda heavy into Portal this last week. Both of them.

Stanford And Silicon Valley, Sitting In A Tree

Ken Auletta on the thin membrane separating Stanford University and Silicon Valley:

David Kennedy, a Pulitzer Prize-winning historian who has taught at Stanford for more than forty years, credits the university with helping needy students and spawning talent in engineering and business, but he worries that many students uncritically incorporate the excesses of Silicon Valley, and that there are not nearly enough students devoted to the liberal arts and to the idea of pure learning. “The entire Bay Area is enamored with these notions of innovation, creativity, entrepreneurship, mega-success,” he says. “It’s in the air we breathe out here. It’s an atmosphere that can be toxic to the mission of the university as a place of refuge, contemplation, and investigation for its own sake.”

Auletta’s article nails whatever low-frequency sense of despair you might have heard thrumming through my piece on Silicon Valley earlier this year.

Related: Stanford’s Design School as seen by Stanford’s Business School.

NCTM 2012 Schedule

My Session

I’m going to put this talk on ice after NCTM. If you caught it at either of the California conferences, I’d check out Al Cuoco’s session instead.


There will be a math teacher tweetup on Friday at 6:00PM at The Farmer’s Cabinet.

Other Sessions

With infinite time and infinite clones I’d catch all of these sessions. The usual biases: nothing with an exclamation point in the title, no TI technology, no SMART technology, no vendors. If I missed anything (maybe even your own session) please make a case in the comments.




BTW: Ihor Charischak has culled out some promising sessions in the technology strand.

Best Of 101Questions [4/21/12]

My five favorite listings on 101questions this week:

  • Soccer Ball Inflation, Nathan Kraft. My students are promiscuous with proportions, applying them to any situation where they have one known relationship and one unknown. That’s my fault. A proportions unit ought to feature unproportional relationships right alongside the proportional and in similar quantities. So here’s a good one from Nathan Kraft. If the small ball takes nine pumps to fill and it’s half the size of the large ball, the large ball will take 18 pumps. Right?
  • Swimming the River, Scott Farrar. Resultant vectors aren’t always easy to visualize, which makes this invaluable. If I used this in a class, I’d probably cut it halfway so students could calculate the girl’s odds of making it to the rock. Pairs well with Crosswind Landing.
  • Tuba Echo, Nathan Kraft. So you have a guy honking away on a tuba, facing a wall that honks back. Gold
  • Google Calc Error, Carl Malartre. For whatever reason these are pretty risky. Why is Carl at 80% with this while James McKee is stuck in Skipsville with Temperature Conversion?
  • Please take a seat, Gulliver, Statler Hilton. My question: “How tall is the person who would sit there? How much would she weigh?”

Plus my own listings: