Math = Love: Finding and Interpreting Slope INB Pages

Wednesday, February 25, 2015

Finding and Interpreting Slope INB Pages

This has been a weird year of teaching for me.  It's year three which means that I feel like I'm kinda starting to get the hang of this whole teaching thing.  But, at the same time, I see so many areas that I desperately need to improve in.  I go back and forth between feelings of excitement over being able to parts of lessons and notebook pages from previous years and feelings of disappointment in myself for just reusing things from previous years and not making them better.  My notebook pages this year look a lot like last year's with a few tweaks and new additions.

I haven't really done a great job of blogging notebook pages this year because it's seemed like I'd just be sharing the same stuff all over again.  But, I do need to make an effort to share these new pages with y'all.

Here are two new pages I created this year for Algebra 1's unit on slope.  

Last year, I let my students design their own notebook pages over finding slope from a graph.  While this let me see what they knew and understood, it did not lead to pretty notebook pages that they could later reference.  I knew this needed to be remedied this year!

I have posters in my classroom that say WWSDS?  This stands for "What would Slope Dude say?"  After students use rise/run to find the slope and write their answer, I ask them to consider WWSDS?  Then, they compare their answer to what Slope Dude would say.  If their answer was positive two thirds and Slope Dude would say "Nice Negative!" this is a sign of a problem.  I've blogged more about Slope Dude and these posters here

One of the standards for Algebra 1 in Oklahoma is that students are able to interpret the meaning of the slope and intercepts of a graph.  I feel like I've always sort of rushed over this before.  This year, I decided to spend an entire 50 minute class period just interpreting the slope of graphs and tables.

We took a few notes about interpreting slope.  Then, we got lots of practice in the form of a poof book!

Here's my notes over interpreting slope:

I gave students a sentence format to use to interpret slope.  For each example in the poof booklet, we used this sentence framework.  My students in the past have regularly fallen for the incorrect multiple choice option that leaves out the word change in the interpretation.  I was hoping that by having my students write this sentence a crazy amount of times that the word change would become ingrained in their memories!

Outside of Poof Book:

The inside pages of the poof booklet are tables and graphs that I stole directly from EOI sample problems provided by the Oklahoma State Department of Education.

So, I guess I should have put these two pages at the beginning of the post.  Oh well.  I think you can figure out what order these pages actually went in our notebook based on the content.  :)

The Slope graphic organizer was a reused page from last year.

However, the finding slope from a table or points notes are new.

I always start teaching slope with the "scary textbook definition."  Students are freaking out.  They think they're never going to understand this new topic.  Then, we slowly break apart the fancy definition into something that is much less scary and more familiar.  Eventually, they realize that slope really isn't that bad at all.

There are a lot of days where we just take plain old notes in my classroom.  Not everyday is filled with foldable fun.  Maybe someday...

I did find a way to incorporate a foldable into this lesson, though.  My students used our new handy dandy foldable vertical number lines to find the differences in the x values and the y values.  

We only do slope as delta y/delta x or change in y over change in x.  The slope formula (y2-y1)/(x2-x1) has been banned in my classroom for two years now.  And, it's one of the best decisions I ever made.  When my students have to think about what's happening on the number line, they are much more accurate and careful than when they try to remember integer rules that they never really learned in the first place.  
I'm also a total convert to vertical number lines now.  They're awesome.  Of course I still just have a horizontal number line in my classroom.  Next year, though, I will have a vertical number line on the wall, too.  It's a must-have now.  

I love that students can fold out the number line when they need it.  Fold it back when they don't. I wrote more about the vertical number line here.  

Want to download these pages?  Click here.


  1. The vertical number line idea is AMAZING. I'll be reviewing slope sometime in the next month or so... Definitely adding this to my INB!! Thanks for sharing :)

  2. Totally sums up what I did with my kids this year. Thanks for sharing.

  3. Sarah,

    Do you teach slope first or functions? What dictates the order for you? Have you ever thought of teaching it the opposite way?


    1. I teach functions first, then slope. This lets us develop a lot more vocabulary before delving into slope. Though, I think you could do it the other way, too.

    2. Wow! Why would you say this? I am flabbergasted!

  4. I love the way this goes, but keep in mind the term "puff puff positive" can be taken as smoking. I used this lesson yesterday with my 8th graders and that's what they got out of it. We changed ours to say "perfect positive" instead, but it sure did make me blush. We all got a nice laugh out of it, but I'm just glad none of my administrators were in my room.

    1. Funny, I've never had a student mention this. I guess it just goes to show that each group of students is different! Glad you found a way that works for yours!

  5. I feel crazy, but how did you put your "poof" booklet together. Is there a way to fold it and it look like that, or do you cut it apart and put it together?

    1. This post has instructions:

  6. Thanks for all your great ideas and INB pages Sarah!! My students are rocking slope and they love Slope Dude :)

  7. Hi Sarah--Thank you so much for sharing all your materials! You're doing an amazing job!!
    Quick question: when you mention teaching slope as "change in y" etc. and using a number line and not the slope formula, how do you address the sign of the slope with the number line?