bored of education

Disney's Holes as a Math Movie

I am always on the lookout for movies to show in math class. The history and English teachers are always watching movies. It's only fair that math teachers get to watch something once in a while... (So if you know of any, feel free to post a comment.)

Holes, based on the book by Louis Sachar, is about Stanley Yelnats who is sent to Camp Green Lake for a crime he didn't commit. He is really there because of his family curse brought on by his "dirty-rotten-no-good-pig-stealing great-great-grandfather." (I think I got the quote right. My copy of the movie is at school.)

At camp he digs holes "to build character." He also learns more about his family curse as well as the curse on Camp Green Lake...

It's a great movie even without the math connections. But here are some ideas for practice in algebra. (The last questions even lead into the concept of the derivative.)

One question you can ask before watching the movie:

How much dirt is in a hole that is five feet deep with a diameter of 5 feet?

Answer:

None! There is no dirt in the hole after it is dug... Haha!

Here are some more serious questions to get your students thinking about algebra. If these are too difficult, specify the length of the shovel.

The character X-Ray uses a shorter shovel than the others so he gets to dig smaller holes. Each hole has a diameter of one shovel length and a depth of one shovel length.

If his shovel is 10 percent shorter than the others, how much less dirt does he have to shovel?

If his shovel is 20 percent shorter, how much less dirt does he have to shovel?

What if it is x percent shorter?

For small percentages, is there a linear approximation to the previous question?

At what percentage does the linear approximation no longer work?

As I think of additional questions I will add them. If you can think of any feel free to post them in a comment.

Update: There are other educational resources related to Holes at eduscapes and at The Hole Truth.

Update II: Here are links to Amazon's pages for the movie:

Full Screen Edition

Wide Screen Edition

Carnival of Education

Yesterday, I submitted my observations about the NCTM Conference to the Carnival of Education. This morning they posted a link to my site. So far, 21 people have followed the link to visit.

It's really cool and kind of scary that strangers are reading my thoughts. I wonder if I should have taken steps to remain anonymous... Oh well, it's too late now.

I suppose it will be fine as long as my principal doesn't find out that other principals want me to move to New Mexico.

By the way, what is there to do on the weekends in New Mexico?

Update: As of 10:45 California time, I've had 41 visitors from the Carnival of Education.

Math Teachers' Lounge

Update: Here is an alternate title suggested by reader:

Math Teachers Occasionally Lounge, and When They Do They Really Deserve To

Because of my experience at the NCTM Conference. I've decided to use part of my blog to help high school secondary math teachers exchange ideas and resources for FREE. So if you have any cool warm-ups, lesson plans, games, etc. that you would be willing to share please email me at damon_hedman [at] yahoo [dot] com. (The [at] and [dot] are supposed to keep spam-bots from finding my email. I don't know if it works or is even necessary.)

If you need cool classroom ideas check back around midsummer. (It will probably take me that long to organize and post my own cool stuff as well as any that is sent to me.)

Meanwhile I've set up a yahoo group (at groups.yahoo.com/group/mathteacherslounge) to facilitate discussions between high school math teachers.

Loitering at NCTM

Last week I spent my spring break loitering at the math teachers conference in Anaheim. I learned so much it's been hard to contain it all. Here are some of my observations:.

I learned that no-one checks your badge to see if it's counterfeit.

If you stay at the hotels, the daily parking is $16 where if you only drive in for the day it is $8. And if you park in Garden Grove and walk, it's free. I would think the nightly hotel bill of $160 would offset some of the parking expenses.

I was pleasantly surprised when the parking attendant remember me from my visit two days earlier.

If you buy a hot dog and soda at the Anaheim Convention Center it costs $9.50. I would think the $180 registration fee would offset some of the hot dog expenses.

I learned that $180 is actually inexpensive for a conference of this size and that the many vendors probably made up the difference.

You can get a lot of free stuff from vendors who want you to spend your school's money on a lot of expensive stuff.

There are schools that can't afford the expensive stuff so their teachers spend their own money on less effective substitutes.

I learned that far too many teachers spend their own money on less effective substitutes.

A cheerleading competition was scheduled next door. (I assume it was to cheer on the math teachers.)

People came as far as Australia. (To the math convention. I don't know about the cheerleading one.)

I met a principal that wants me to move to New Mexico. (I assume it was to teach there.)

I met a teacher from Compton, California that doesn't think merit pay based on student performance is fair when she has Algebra classes with 40 plus at-risk students while other districts have more motivated classes of thirty students or less.

She told me that she is considering quitting.

I met a surprisingly large number of people who were looking for the boat show. (They must have walked in from Garden Grove and didn't see the directions.)

I discovered there is free wireless available on the second floor of the Anaheim Convention Center but not anywhere else.

I did learn some math teacher stuff but won't bore you with the details.

I learned so much I am definitely going next year when it is in St. Louis.

NCTM Conference

Today was the first day of the NCTM conference for math teachers.

There was so much information it's going to take me awhile to process it and adapt relevant parts for my classroom. I was hoping to have a ton of new ideas that I could use on Monday. However, it will take some time to adapt the things I learned to my own style and procedures. (Its also kind of unfair to my students to change too much in April...especially grading assessment policies.)

I did have one idea I could begin right away. There were dozens of seminars I was unable to attend. I decided to email the speakers to see if they could email me any of their materials. I'm especially interested in seeing other teacher's rubrics for grading notebooks, journals, presentations, group work, etc.

At first I was only interested in getting those materials to adapt for my own classroom. Then I realized I could post them on my blog--with the author's permission of course. I'm not sure if any teachers would be willing to, but it's worth a try.

NCTM Conference

Last weekend I received my materials for the NCTM conference. (For the uninitiated that stands for the National Council of Teachers of Mathematics--or something like that.) It should be a wild party. You know how math teachers are when they get together. But remember, what happens in Anaheim, stays in Anaheim...

I am looking forward to the networking opportunities. There are only 4 math teachers at my site and it will be good to meet additional people and see what they do in their classroom. (Who knows, I might also learn about available jobs... If my principal is reading this, I'm only kidding.)

I'm also looking forward to the seminars. We approach Math Education in terms of problem solving. The idea is that we give students real world problems and coach them through finding the solution. They develop their own strategies for solving the problem as well as their own understanding and appreciation of the math concepts. I think its called inquiry based learning.

Anyway, I'm still trying to figure out the best way to use this method. After all, I learned the old fashioned way with lectures followed by examples of applications when there was time. There are about 20 seminars related (in some way) to this approach. I wish I could attend all of them but I'll have to settle for a few.

If I have time I'll post the highlights here.