Thursday, April 14, 2011

Linear Equation Posters

 As you know, I recently attended a co-teaching conference.  Once of the things that I learned from the conference was to get the students up and moving if possible.  That's how this poster activity was born.

I created 6 posters where difference pieces of information were given on each one.  The black ink is what I wrote.  When the students came into the room that day I had the posters is different locations.  I put the students into groups of 2 or 3.  Each group received a different color marker, this way I know which group wrote what.
The students had 2 minutes to pick one of the five empty rectangles and fill it in as it related to what I wrote in black.  
Then the students moved to the next poster and filled in one of the four rectangles that were empty.  
As they moved from poster to poster, they were also instructed to look at the work of previous groups and make (appropriate) comments or corrections.  Writing "you're an idiot" is not appropriate.

Given: x- and y-intercept

Given: Slope-Intercept Form

Given: Situation

Given: Standard Form

Given: a table of values

Given:  the graph of a line


Pros:  The students were up and moving, I could see what they were writing,  I could easily see and hear misunderstandings, and the students were having good discussions about algebra.

Cons:  I put the posters too close together because my wall space is limited.  Next time I will make use of my table.  Just because they're posters doesn't mean they have to hang on the wall.  I had the posters about 4 feet apart, but this meant the entire class was crowed in the front of my room.

One misunderstanding that showed its ugly head -->  Students didn't know the different between the x-intercept and identifying what x represents (such as the situation).

Friday, April 8, 2011

Barbie Bungee Jumping

I've been toying around with this activity for a few years now, but I've never had a class that I trusted enough to cooperate and do this.  This year the students are no different, however, I am co-teaching this class and there are two more eyes to help with crowd control.  

This activity was used with a 9th-grade Algebra 1 class.

The activity in a nut shell:
1) Students determine how far Barbie bungees with up to 10 rubber bands.
2) Students determine how many rubber bands are needed to have her jump from a higher height, but using their knowledge of regression equations, slope, and y-intercept.
3) Finally, students bungee their Barbies from that height.

The original idea came from Illumination from NCTM.

Here is the packet that I created for my students.

We started in the classroom and the students used up to 10 rubber bands.  A few problems that I noticed along the way.

- Students had difficulty finding average.  Yes, average.  They completely forgot about the order of operations with the calculator and would type this in:  50 + 49 + 51 / 3.  They neglected to use parenthesis or the ENTER button.

- The students assumed that it's okay to round.  No! No! No!  Not when Barbie's life depends on it.

 - The students did not double check each other's work.  One student solve the equation incorrectly and the rest of the group assumed she did it right.  

The big day - when it finally stopped raining we were able to bungee the dolls from a 14-foot height.

The results - Two of the groups did well. Their Barbie came within inches of the ground.  Three of the groups didn't have enough rubber bands for the reasons listed above.  Three of the other groups "killed" their Barbies with too many rubber bands.  I believe their mistake was in the classroom and not accurately measuring the bungee distance.


I will do this activity again.  Not only did it help students with concepts of linear equation, but it was a nice review of estimation, average, and rounding.

The students were more well-behaved that I thought they would be.  I believe this is because they were very interested in the activity.  This helps with one of my problems - being afraid of my students.  Not afraid for myself, but afraid of lack of cooperation.  Perhaps if I would show some trust more often, I would see more cooperation.  Maybe.

What I would do differently next time.
I will need to emphasize the importance of not rounding and the importance of measuring accurately.

Wednesday, April 6, 2011

Student Journals

Classroom Products Warehouse just sent me an e-mail that offered my 10 free math journals with any purchase, and no minimum requirement.  Here is a link to check out these math journals.  If you haven't realized by now, I like to create my own classroom products for next to nothing.  So, I checked out the journals they were offering and decided to see if I could duplicate them.  Here is the result:

I intentionally leave the front cover blank so that students can create their own design.  I do insist that their name is somewhere on the front.

Inside I have lines for journaling and a grid for graphing.  I also like to leave out the axes.  I feel that students should decide if all four quadrants are necessary or if they should only use the first.

So, here's how you make these things.  First print out the journals.  The first 2 pages should be back-to-back, as well as the last two pages.

I printed page numbers at the bottom of each page.  Take the paper with pages 4, 7, 8, and 3 on it and cut it like the photo above.  Make sure to make cuts at the top and bottom.

Take the other paper (pages 2, 5, 6, and 1) and cut a line down the middle like the photo above.

Now, let's go back to the first paper (pages 4, 7, 8, and 3) and hold page 4 like this (4 is inside the roll, 3 is on the outside).

Take the first paper (the one in your hand) and insert it into the second paper.  The second paper should have pages 2 and 5 facing up.

Pull that paper all the way through and there you have it.  Your very own math journal on the cheap.

Monday, April 4, 2011

Tire Calibration

I posed a question to my "lower" pre-calc class today.  I started by telling them that the problem was really hard and that I wanted to determine who the "smarty-pants" in the class were.  This is a class full of students who won't quite make it to Calculus.  Most of them have trouble understanding material, they prefer to memorize.  So I take special care of this class and make sure I show them why.  I rarely teach them any tricks as they will rely of those and forget why.  Anyway, below is the problem and I am proud to say that about half of the students got a correct solution and beyond that they were proud of themselves too.

As you are driving down a road in your car you see that your speedometer shows a velocity of 45 mph.  However, you know that you have the wrong tires on your car.  The tires you have on have a radius of 18 inches and your tires should have a radius of 16 inches.  This means that even though your speedometer reads 45 mph, you are truly going faster.  What is the true linear speed of your car?  Show and explain all of your work.

Sunday, April 3, 2011

Hot Dog Cookers

Last school year, while looking over my curriculum map, I came across my unit on conic sections.  The first question that crossed my mind was, "Why is this important to learn?"  In my entire life, I have never used conic sections unless I was teaching it.  It then became my mission to find a reason for my students to learn conic sections.

In my research I found parabolic solar cookers and I was hooked.  I ran the idea past my colleague, who teaches the same course and we immediately went to work.  During the last in-service day of the school year we constructed this solar cooker.  In the afternoon we purchased a pack of hotdogs and set out to see if this was an idea for our students.

After eating our HOT hot dog, we started to devise a plan in our heads, and "Hot Dog Day" was born. This May our pre-calc classes will be taking their cookers outside to cook, you guessed it, hot dogs.  

Have I done this yet?  No, but I was too excited to not tell you about it.  I will post again later but wanted to throw this out there now.
Currently our students are determining their focus point and just how exactly they are going to construct their cooker.  Our students are excited beyond belief and, for the first year in the history of teaching this class, they understand the importance of conic sections.  I too have found a reason to learn about them.
Now, I need a reason to make ellipses important....hmmm...

Friday, April 1, 2011

Trigonometry Tangram Puzzles

I think that Tangram Puzzles are pretty neat.  Once in a while I try to figure out how to create certain images/shapes that I see online.  But my students don't really enjoy this activity.  And I can't argue with them.  There is a reason I only sit down and try it once in a while.

However, I did create an activity where students will use tangrams and trigonometry to create a certain image.  I will apologize that they are hand-written, but I wrote these years ago and never had the energy to type them.

Tangram Activity Link


Tuesday, March 29, 2011

White Boards and Page Protectors

In my last post I wrote about individual white boards on the cheap and what backgrounds to make.
Here are a few of my favorites, feel free to use these as you wish:

1) Algebra 1 - I did a lesson on Graphing Inequalities recently and the students used these in their page protectors.

2) Trigonometry - Filling in degrees and radians on the unit circle.

3) Trigonometry - Graphing Trig functions.

This post is a work in progress.  I will add more as create them.  Also, feel free to send us links to yours in the comments sections.

Sunday, March 27, 2011

Individual White Boards

I LOVE individual white boards.  My students LOVE individual white boards.  But I find them to be expensive and limiting.  This past fall I attended my first NCTM Conference.  While walking through the vendor section, I found flimsy individual white boards and bought them up (30 of them for about $15).  One side was blank and the other side had the coordinate plane on it.  They work wonderfully, but I bought them with my own money.  Plus I bought the markers to go with it (about $10 for 30), which were dried out by the way, and I purchased wash cloths as erasers (about $10 for 30) all with my own money.
I didn't brainstorm this idea long enough.  As I walked around the vendors a little more, I noticed that a few had "boards" where the background could change as I wanted it to.  They are called SmartPals and you can see a picture of them below.

You can insert any background you want.  Perhaps I only want the students to graph in the first quadrant.  Or maybe I want them to fill in a table.  It's great when my students are graphing Trig equations because I can change the step on the axes.  So, this solved my problem on the limitations, but not the price.

There is also a brand called The Communicator Clearboard and you can see these below.  This one is different from the SmartPal in that it only has an opening at the top:

Recently, I was attending a co-teaching conference (more on that later) and at one point the presenter handed each group a disposable plastic plate and a dry erase marker.  Bingo!  The students could use these plates as individual white boards and that solved my financial problem.

But I still didn't have a way to solve BOTH of my problems at the same time.  Then it hit me - PAGE PROTECTORS!!  All I have to do is print out the background that I want and have the students insert them into a page protector and wha-la.  Individual white boards on the cheap and no limitations.

Okay, let's be real.  Let's talk about the drawbacks:
1) It's not easy to get those papers in the page protectors.  Some students will become frustrated.
2) They are flimsy.  The students will have to use 2 hands to hold them up so we can see it.  I suppose that I could insert a thin piece of cardboard to make it more sturdy, but that takes us back to problem #1.
3) I still need to purchase markers when they dry out and wash cloths (and wash them once in a while).

Now it's your turn:
1) What background would you create for these "white boards"?
2) Can you think of anymore drawbacks?
3) Have you tried this?  How did it go?

Saturday, March 26, 2011


Hi there!  My name is Nora and I teach high school mathematics.  This blog has been in existence for years, but only in my head.  The last thing I need is another thing to do.  However, I have a lot of ideas that I believe are worthwhile and want to share them with you.
One of the main reasons for creating this blog to to get your honest feedback.  Don't hold back please.  If you tried one of my ideas and it totally bombed, I want to know about it.  Perhaps we (me and the readers) can find a solution to make it work, or perhaps it should be scrapped entirely.  Likewise, if you try one of my ideas and it was a success, I would love to hear about that as well.  I'm always looking to pat myself on the back.
A little bit more about me.  I have been a classroom teacher since 2000.  I currently teach algebra 1 and pre-calculus.  However, my schedule changes every year.  In the past I have taught pre-algebra to 7th and 8th graders, Algebra II, and Calculus.  Did you notice what is missing?  Yeah, Geometry.  I have never been assigned to teach Geometry.  It is my goal to one year speak up and be assigned that course.
Anyway, I hope that you'll join me in the quest to be a better and more adventurous teacher.