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Year: 2008

Total 265 Posts

So Happy Together #5

By • March 31, 2008 • 13 Comments

I’m one day out of a presentation to the Oakland Teaching Fellows on digital projectors (working title: PowerPoint – Do No Harm) and really excited about it. A lot of these folks are right around my age, some older, which’ll make for different dialogue than what I’m used to in my high school classesWhich usually hovers around who can fart loudest into the speakerphone..

This last note-to-myself circles around classroom management and how much easier it is to keep a large group of students focused with a digital projector, presentation software, and wireless remote than without.

One Idea:

Classroom Management: The Triangle Offense

Like This:

Let’s say you’re in a short lecture block. If your only tools are a chalkboard/whiteboard and chalk/marker, you’re tethered to the board.

You can draw a bit, write a bit, ask questions a bit, but always at the board. If Llewelyn loses focus, you can wander to his desk, maybe ask a softball question to pull him back in, but then you’ve gotta return to the board, all while the kids farthest from you drift off.

Your classroom dot plot looks like this:

Let’s say now you have a digital projector and a wireless remote and you’ve already loaded some discussion-worthy diagrams into your presentation software. You’re mobile.

You walk to the far side of the classroom and address the board. Your focus directs theirs. You toss a question at the opposite side of the room pulling them into your locus.

Your question, the projected image, and the kid answering the question, are three vertices of a triangle inside of which classroom management is a relative non-issue, inside of which you all have really, really good focus.

It’s the triangle offense, and it’s very effective.

Previous Editions:

Help Me Get Away With This

By • March 30, 2008 • 21 Comments

Mean, median, and mode are each important, each easily mistaken for the others, and, depending on context, misleading or completely meaningless.

I came across a scenario yesterday which highlighted their differences and limitations a little too perfectly:

  1. Consider every human being in the world.
  2. List each person’s total testicles.
  3. What is the mean, median, and mode of that list, and what do they mean?

Is this even worth the trouble? If you aren’t trying to shock or pander to or titillate your students, are testicles fair game? ‘Cause the implications and extensions are really awesome here.

Like: the average human being has one testicle.

Or: the median number of testicles is either zero or two depending on gender majority.

And: the median and the mode will be the same number except under a few (also awesome) conditions.

How do I avoid panicking my principal here?

[via Jim Ray’s cool tumblog]

Keeping Me Up At Night

By • March 28, 2008 • 4 Comments

Dina:

If you’ve got a dozen well-trained educators on this blog asking double the amount of critical questions about this cute little NAEP Excel doppleganger, most of which questions completely debunk not nuanced “implications,” but the very parameters of one’s x (math curriculum being assessed) and y (use of technology) values– I mean, come on. The *X and Y* values?!? Doesn’t that indicate on its face that we should throw out the whole damn graph?

She’s right, though the questions undergirding this sketchy data still intrigue me:

  1. What constitutes computing use in fourth-grade math? Rote repetitive drill software? Number Crunchers?
  2. What elements of math’s 12-year plan are outmoded, concessions to universities and textbook publishers? Does it lack coursework? Does it comprise too much coursework?
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