## Posts tagged ‘Vi Hart’

### Vi Hart, Sierpinski, and the Chaos Game

My kids love to spend the last 20 minutes before lights out doing math with daddy. Often, as an alternative to reading another chapter from the *Magic Treehouse* series, they will ask, “Can we do bedtime math tonight?”

Unfortunately, the materials at Bedtime Math quickly lost their luster — if not for Alex and Eli, at least for me. The problems are based on current events, but they are little more than traditional textbook exercises. Sorry, that’s just not the math to which I’d like my sons to be exposed.

So instead, I’ve been developing my own ad hoc bedtime math curriculum. Last night’s lesson was the Binary Trees video from Vi Hart’s Math Doodling series.

For 3 minutes, 48 seconds, the video had the boys’ rapt attention. When it ended, Eli turned to me. “Well, *that was pretty cool*,” he said.

This afternoon, we explored an extension.

- Draw equilateral triangle
*ABC*, any size you choose, on a sheet of paper. - Randomly pick a point
*Q*on the same sheet of paper. - Now, randomly pick a vertex
*A*,*B*, or*C*, and place a dot at the midpoint of the segment that connects*Q*to that vertex. (But don’t draw the segment. That’ll just make things messy.) - Again, randomly pick a vertex
*A*,*B*, or*C*, and place a dot at the midpoint of the segment that connects the previous point to that vertex. - Repeat Step 4 thousands of times, or at least enough times to see a pattern emerge.

We played this game for a little while using a 12-sided die to determine the randomly selected vertex. A roll of 1-4 chose *A*, 5-8 chose *B*, and 9-12 chose *C*. Interest was starting to wain after 20 rolls, so we paused for a question:

Notice that most of the points occurred within the triangle. If we continue rolling and drawing points, do you think any more points will occur outside the triangle?

The answer is **no**. All points will occur within the triangle.

If you haven’t seen this game before, it’s called the Chaos Game. And if you don’t have interest in rolling a die 2,496 times to see what happens, you can open the Chaos Game spreadsheet. The values in column B are the *x*-coordinates of the points, and the values in column C are the *y*-coordinates. Change the values in B1 and C1 to pick a new starting point, and hit F9 on a PC or fn+F9 on a Mac to generate a new set of data.

Cool, huh?

### Why Did Vi Hart Go to Khan Academy?

I love Vi Hart. And with over 300,000 subscribers and 25 million views on her YouTube channel, I’m clearly not alone.

But perhaps you don’t know who she is. Maybe you’ve been living under a rock. Maybe you’re still using dial-up. Or maybe you’ve just been posing as a mathy folk, only visiting this blog because you think the author is hot. (Of course, you’d be correct in your assessment, but you shouldn’t let hot authors guide your tour through the blogosphere.)

If you don’t know who Vi Hart is, you can check out her Binary Trees video below (from her now famous Doodling in Math Class series).

Pretty awesome, huh?

In the video, she makes the following statement:

…if the [math] curriculum wasn’t so appalling and the teaching methods weren’t so atrocious, you wouldn’t have to entertain yourself with these stories and games.

She also implies that many math classes are

…fuzzy, unfocused, and altogether not very good.

Some educators don’t like these videos. Some don’t like that a brash, young woman is criticizing what they do and how they do it. Some find her statements offensive.

Not me.

I think she’s spot on.

Too many math classrooms still look like the math classrooms of yesteryear, devoid of excitement and technology and filled with endless hours of meaningless practice.

But here’s where I have trouble. On the About Vi page of her site, she says:

I am now a full-time mathemusician at Khan Academy! It’s pretty exciting.

If she is truly opposed to appalling curriculum, why would she work for a company that creates the video version of a 1950’s textbook?

Maybe I’m being too harsh. But I don’t think so. Though she now creates recreational math videos for Khan Academy that are awesome, the vast majority of videos on the site are nothing more than math lectures of topics that probably should have been removed from the curriculum years ago. When I asked a colleague his thoughts, he had this to say:

Vi’s videos show such polish and cleverness, while Khan’s were so obviously made by someone who just took an exercise from a textbook and sat down at a computer and improvised. About the only thing [Khan Academy] has going for it is that it’s free. I suppose it can have some good use in getting kids an opportunity to learn and practice skills they need, but having them practice skills for no particularly good reason… it’s just reinforcing everything that’s wrong with math education.

In her Binary Trees video, Vi Hart makes fun of the boring presentation of exponential functions that typically occurs in math classes. Yet the Khan Academy video Exponential Growth Functions uses the same examples and “atrocious teaching methods” that would be found in many of the math classes that are “fuzzy, unfocused, and altogether not very good.”

So, what’s up, Vi? How can you rail against bad teaching but then go to work for a place that delivers bad teaching in spades? Your work is amazing, and you had such an opportunity. I hope your intent is to make change from within rather than assimilate.

**How do you feel about Vi Hart’s move to Khan Academy? And what do you think about Khan Academy in general?**