Dan Meyer

Total 1628 Posts

I'm Dan and this is my blog. I'm a former high school math teacher and current head of teaching at Desmos. He / him. More here.

Five Favorites — 101Questions [5/26/12]

By Dan Meyer • May 26, 2012 • 16 Comments

Doggie Bandana, Marshall Thompson. Marshall got me good with this one.
Water Power Plant, Bernard. Similar to Windmill. In both cases, I’d like to know if what we’re seeing would power a light bulb, a fridge, or a car. As in, I really want to know. No math teacherly pretense here. If you can help me answer that question, I am your eager student.
Snow, man, Patrick Brandt. I skipped this one initially, but Patrick’s question has been gnawing at me since I saw it. Can anyone suggest a redesign?
London Eye, Edwin Ulmer. I’ve been looking for just this kind of clip for a long while. Three cheers for Internet-based collaboration.
Shoot the Gap, LDH. Recently, I expressed a sense that posting video of GGB / GSP applets tends to miss the best parts of both. This one is different.

My own listings:

At the end of a session in Toronto just now somebody asked me how much time it takes to come up with these kinds of tasks. “More or less than when you made tasks on paper?”

“Definitely more,” I said. But, brother, can you see I’m trying to suppress some kind of goofy smile in Popcorn Picker? Same with Coffee Traveler, where I’m grinning off screen. At a certain point, I stopped coding this kind of production as “work.” No disrespect at all if that’s not your thing.

Data Dump:

Do people who upload more have higher perplexity scores? No, they don’t. I would like to see an animation of those points over time, though.

Good Questions For Good Contexts — Ignite #openedu

By Dan Meyer • May 23, 2012 • 12 Comments

If anyone ever asks you to give an Ignite talk, say yes. With twenty slides auto-advancing every fifteen seconds – ready or not – it’s a wonderful, miserable format. I’ve given a handful and each one has helped me get a stronger grip on editing, illustrating, and public speaking. Here’s the Ignite talk I gave at O’Reilly’s #openedu confab yesterday:

The short version is this: lousy contexts and lousy questions are easy to find. Good contexts and good questions are scarce. I’m working on one solution to the good contexts / good questions shortage that isn’t even in the same ballpark as “perfect,” but it’s a start.

Scott Farrar, Dan Anderson, Frank Noschese all made contributions to this talk. Thanks, buds.

These People With Their Dogs Wearing Bandanas

By Dan Meyer • May 23, 2012 • 15 Comments

McGraw-Hill:

Kachima is making triangular bandanas for the dogs and cats in her pet club. The base of the bandana is the length of the collar with 4 inches added to each end to tie it on. The height is 1/2 of the collar length. If Kachima’s dog has a collar length of 12 inches, how much fabric does she need in square inches? If Kachima makes a bandana for her friend’s cat with a 6-inch collar, how much fabric does Kachima need in square inches?

I’m not a pet owner so somebody please set me straight: is pet apparel a productive context for mathematical inquiry? Does PETA know about this?

Previously: Unnatural Currents

Featured Comment:

Kari:

Yes, they make triangular bandanas for dogs, single ply. Usually cut with zig-zag scissors. My dog comes home from every stay at the kennel looking like a boy scout. every. time. This is still a terrible problem though.

Gender Bias On 101questions

By Dan Meyer • May 22, 2012 • 64 Comments

Elizabeth:

Am I imagining it, or are the participants (posters and respondents) mostly male? I’d love to be wrong about this. If I’m not wrong, then why would that be the case? And more importantly, has anyone noticed whether there is there any difference in class participation between female and male students when these are used in class?

I don’t ask for your gender during the registration process so it’s hard for me bring any data to bear on the question. But if I allow myself some conservative guesses, it seems that at the time of this writing:

the top ten most perplexing users are all male,
nine of the top ten most perplexing first acts were uploaded by males.

So help me, I can’t figure out how the interaction on the site (ask a question and click “skip”) or the nature of the tasks (a context and a question) preferences men. The reviews are all blind, too. I’m looking at a photo. Maybe it was uploaded by Candice Director. Or maybe by Dan Anderson. It’s impossible to know until later.

I’m highlighting Elizabeth’s comment to see if anyone can help me figure this out. I’d rather this didn’t turn into a general complaint window, though. I’m interested in locating the source of any gender bias, not in airing out any other grievances.

BTW: My adviser has done a lot of work in gender and math. I should probably check in.

Featured Comment:

Too many. A really great discussion down below. Here’s a link to my summary.

Five Favorites — 101Questions [5/19/12]

By Dan Meyer • May 19, 2012 • 14 Comments

Circle or Polygon? Scott Farrar. This thing is poised to take over the all-time list once it crosses the 25-response threshold.
Lemonade, Christopher Danielson. On some other site – let’s call it Bizarro 101questions – Danielson uploaded a video in which he dropped a can of concentrate into each of those containers and started filling them with water.
Megalodon Tooth, Jake Jouppi. I know I declared a moratorium on this kind of imagery (which is all over the site at this point) but think about the size of that shark, okay?
Ping Pong, Bob Lochel. Great first act with strong implications for the third.
Roller Coaster Steepness, Tom Ward. An excellent supercut of roller coasters that asks the student to first decide which one feels steepest (that’s a low rung on the ladder of abstraction) before using mathematical analysis to determine which one actually is steepest.