Math = Love: Inequality Card Sorts

Tuesday, January 3, 2017

Inequality Card Sorts

Today, is my students' first day back from break.  Yesterday, we had a professional day which was mostly a "work in your room" day.  I took this time as an opportunity to create a couple of new card sorts for my Algebra 1 class.

Before break, we were focused on graphing lines from equations and writing equations from graphs. I blogged about our interactive notebook pages for this unit here.  The last part of our current unit has a switch in focus to graphing and writing inequalities.  My students have already been exposed to one-variable inequalities, but my students haven't seen them in a while so we need review.

My "includes" vs. "excludes" poster set should come in handy for this!


My plan is to put students in pairs and start them with a one-variable inequality card sort to help jog their memories and get them talking.

Each group with get a set of five number lines and inequalities to match together.

Hopefully, my students will be able to be successful with this "review" card sort.  I will ask students to share with the class any strategies they used to match up their number lines and inequalities.  

Then, I am going to do something scary.  I am going to give them the next card sort and ask them to match two-variable inequalities and graphs without having done any teaching regarding two-variable inequalities.  

I want to see what my students can do without any input from me.  I am inspired to do this by my recent reading of Make It Stick (affiliate link).  

The book claims that trying to solve a problem before being shown a solution leads to better and deeper learning even if errors are made in that first attempt.  In the past, I've been a "how will they know how to do it if I don't show them?" teacher.  But, I'm trying to change.  I'm trying to challenge my students to think on their own.  Then, we will examine their solutions and talk through them.  I think my students will be more attentive when we do get to the note-taking stage of our lesson since they have already attempted a problem on their own.  

Here's the two-variable inequality card sort I have created for them to attempt.  

Another thing I am trying for the first time this year is looking at different versions of the same equation/inequality.  Instead of matching a bunch of different inequalities, I used the same basic equation/inequality: y ? 2x + 1.  I hope this helps students focus on exactly what changes when we change the symbol.  

If you would like to use one or both of these card sorts in your own classroom, I have uploaded the files here.

I created the graphs and number lines for these card sorts using which I learned about from someone in the #MTBoS.  I just can't remember who.    


  1. Once again, I love this idea. We go back to school on Jan 9, and have only 2 weeks before we have another 2 week break (don't you just love the Lunar New Year?). When I start my linear inequalities unit, this sounds like an excellent starter and review activity, all in one. I know I will be using this very soon! 🇻🇳😀

  2. I can't wait to hear how the second sort went turned out!

  3. Hi, one thing that I realized on my sorts with graphs is that I forget the graphs get turned around in the bag, so I'm going to start putting labels on my axes I think! Love this idea, but I think I'm going to make my graphs with labels on it:)

    1. I definitely regretted forgetting the labels! Oops...