Saturday, March 30, 2013

Yes, Polly Pocket can Zipline (well, sort of!)

Last week we had Polly Pocket Ziplining day in class!  I showed students a short 15 second video of my 9 year old ziplining, and said that while I'd love to set up a zipline course in our courtyard, legalities would only allow us to create one for Polly Pocket!

I asked students to think about where in the room we could put our zipline so that it was as long as possible.  We've been exploring the Pythagorean theorem so students just needed to be able to visualize where they might find a useful right triangle.

I put several diapers boxes around the room for students to use (which ironically, started a secondary debate about why I had so many empty diapers boxes).  With the boxes and a drawing of a rectangular prism as tools students were able to see some different methods they could use to identify the diagonal of the classroom if they had the measurements for the length, width, and height of the classroom.

They tested their ideas by using the Pythagorean theorem twice and the measurements of the diaper boxes...students used different right triangles in the box and showed that there are multiple ways of identifying the length of the diagonal.

As a final step, they calculated the length of the diagonal of the room and we measured out the string for Polly.  Away she went...well, at least halfway down the zipline.  We definitely need a little bit more of the engineering design process to have a successful zipline...good thing we used Polly and not one of my students :)

Tuesday, March 19, 2013

Can a family really have 1.7 Children?

Can a family really have 1.7 children?  This was the question that came up today when students were exploring measures of central tendency.  They were so convinced that the only possible appropriate answer for the average number of children in a family could be 2 because you can't have a part of a child.

So I threw this their way...suppose we have two communities that are planning for how many schools they will need to build for the children. Each school has a maximum capacity of 1000 students.

Community One: 800 families
Community Two: One million families

What happens in each situation if the community planners use the value of "2" for number of children instead of the number "1.7"?

Great discussion followed...they were really surprised that ".3" of a child could make such a difference.  300 completely empty schools due to poor planning!

Saturday, March 9, 2013

First Barbie Zipline with Polly Pocket

So excited about an activity I'm in the middle of planning.  We are starting 8.G.B.6, 8.G.B.7 and 8.G.B.8- all about understanding and applying the Pythagorean Theorem. In particular, I was trying to figure out how I might approach 8.G.B.7, which says: Apply the Pythagorean Theorem to determine unknown side lengths in right triangles in real-world and mathematical problems in two and three dimensions.  I've done a lot in middle school math with Pythagorean Theorem before, but never really in three dimensions.

Here's what I'm thinking...I really like the Barbie Bungee problem that a variety of tweeters and bloggers were using a little while back.  We're going to try creating the longest possible zipline in our classroom.   My daughter and husband went ziplining in the Caribbean so I was thinking of using a short video from that as the intro.  I think I'll grab several big boxes from here and there so that each group of students can have a box.  Hopefully they will want to design the longest possible zipline in their box...they will have to calculate how long of a piece of string they will need to create their zipline.    Then everyone will figure out how long of a zipline we could make in our classroom.

Not related to the Pythagorean theorem, but an interesting question of acceleration...does the longest zipline make for the fastest ride?  Some of the boxes will result in a steeper zipline...might make for some fun data collection and extension problems.

Any thoughts on other ideas with this?

Monday, March 4, 2013

Twitter and a bag of Vegetables (or two)

Totally inspired by Chris Robinson  @absvalteaching at and his tweet about a bag of frozen vegetables.  We made it into a family experience.  My 9 y.o. and I collected data first by steaming a bag of veggies and then weighing the different types of veggies in the bag.

Cooked Broccoli 3.9 oz
Cooked Carrots 2.4 oz

Cooked Cauliflower 3.2 oz

Cooked: Broccoli- 41%    Carrots- 25%   Cauliflower- 34%