Showing posts with label percent. Show all posts
Showing posts with label percent. Show all posts

Tuesday, April 16, 2013

Percent Game Remixing

In yesterday's post on a percent game, I shared two great GeoGebra sketches that students found. I remixed each of them a little, so I thought I'd share them here.

dhabecker's neat rational number arranging sketch lets students place arrows to try to put fractions, decimals, and percents in order. He has a very clever way to check if the randomly generated numbers are in the right spots.  It notifies students when they've got all 4 right, and I wanted to them to be able to check their answer along the way. So - thinking of Mastermind - I thought about what if it can give the number correctly placed? Since I was doing that I added a reset button and a bit of color. Next I would add a fifth number, as that makes so many more permutations possible.








On GeoGebraTube:
download or applet. (Unfortunately doesn't seem to work in HTML5, because the polygons won't move.)









The other sketch I modified was David Cox's great percent estimation sketch.  Almost immediately on trying it on the Smartboard, the students turned it into a game.

So I turned it into a game with turns and scoring. There's 6 rounds. I thought about forcing players to take turns going first but ultimately just decided to ask them to.

Next  I would be interested in seeing it go from a percent number line to another quantity. So the game asks you to find 38%, but the number line goes from 0 to 630. The percent and the whole would change each time. Worth a go? Probably that's in my head because of David's nice double numberline percent sketch.

On GeoGebraTube:
download or mobile-ready applet.


As always, I'd be interested in feedback on either one of these.

But I'd also be interested in what could help develop a remix culture in GeoGebra.  I learned it (am learning it) mostly on my own by experimentation, from suggestions on Twitter, and googling stuff from the online help. But in the Learning Creative Learning class they put a big emphasis on remixing as a way to learn that gives a lot of support to learners. With my middle school GeoGebraists, they are struggling to do work of value all on their own.

Are you a remixer by nature? What would it take to get you trying it in GeoGebra?

Sunday, April 14, 2013

Percent Game

I was thinking about percents and ways to gain experience with them, in preparation for GeoGebra work with middle school students.

Found a couple of neat percent sketches on GeoGebra...


Nice visualization from jholcomb.
(By the way, GeoGebra has gotten input boxes to work in the HTML5/mobile device. Good going!)






Slick discount problem visualization from Anthony Or (orchiming).






Nice double numberline visualization from David Cox.






But as I looked, the idea for a game came to me, just to give percent experiences. There's no context, really, it's just a race game. No strategy, just rolling random percentages. But the mechanic of smaller roll goes first creates some nice percentage situations, and a lot of games wind up surprisingly tight.

I debated having the students find the percentages to subtract, but decided to make it optional.  There's a short video of how the game works below.

Here it is on GeoGebraTube, for download or for mobile applet.






The test game came out extremely close - most games will be shorter than that. It can be surprisingly suspenseful, though.  All students found it pretty playable, and some got very into it. I think the best benefit might be from playing and then using as a context for problems.

Searching through GeoGebraTube, students found two sketches particularly of interest.


Arrange Fractions, Decimals and Percents by dhabecker (who has quite a few rational number sketches), which lets students arrange form numbers of different form from least to greatest. A few students got quite engrossed in this sketch, and the feel of the sketch is terrific - very much like pieces snapping in place.




Estimating Percents by David Cox, which lets students make a first estimate and then a second estimate with the tens showing. Students were happy to see their % error improve from 1st to second guess, and got better quickly through playing. They also made an impromptu game out of it, and I think that would be fun.



Do you know a GeoGebra Percents sketch that you think supports students' understanding?

Here's the results collected so far. Thanks!

PS> there's a follow up post to this one with two more GeoGebra percent activities.

Monday, April 13, 2009

Portions of 100

Excellent graphical portrayals of percentage at this site:
The World of 100.

I'm imagining using them both to have students think about comparisons with their own community, and looking at the designs as mathematical representations to see if they represent or how they represent the numerical information.