2016-2017 Triangles Unit

Hello all! It's been awhile... I have SO much to share with NOT so much time! :/ I've been busy with my masters class and I wanted to post some of my interactive notebook ideas before Christmas break.

Here are some pages from my interactive notebook over classifying triangles. On the side, we put classify by sides next to the first three and classify by angles on the bottom four.

My resource class completed the following cut and paste chart over classifying triangles. They loved this and some found it challenging!

The following pages are newly created notebook pages over "The Triangle Inequality Theorem." Overall, I loved it and I felt that students understood it more this year than previous years. I will try it with my resource classes on Thursday to see how they do. 

We normally complete the inquiry-based lesson over why the sum of the interior angles of a triangle equals 180 (that is what is to the left of our notes). We also complete an activity that shows why the two remote interior angles of a triangle is equal to the exterior angle. This is my rushed notebook... I will update this post of what is actually in student's notebook. 

I introduce the following pages first before we jump into triangle congruence proofs.

 I am looking forward to using the following triangle congruence foldable with my students this year along with the reference sheet. I switch up this lesson every year for some odd reason :).

After this foldable, then we will jump into triangle congruence proofs! I uploaded my triangle congruence proofs in a previous post: CLICK HERE

Here are some of the files from my triangles unit:

If I forgot to add a file, let me know and I can add it as soon as possible! If I made a typo, please let me know. Thank you to the readers who emailed me about the typos in the proofs book! :)


  1. Hey, I am so glad I came upon your site. You have some awesome, helpful, things. Do you mind to add the Congruent Triangle pages that you use before diving into proofs? Thanks!

  2. Hey Katrina, Great stuff! I intend to add this link it to a my HS Geometry TEKS livebinder if you do not mind.

  3. Could you also add the left side documents for classifying triangles and triangle inequality theorem??

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  5. Thank you so much for this resource! It will help my kids so much!

  6. Out of curiosity, what program do you use to create all your notebook pages? I would love to be able to create some of my own.

  7. Thank you so much for creating all this amazing stuff! Do you have the files on congruent triangles available? I checked above but none of those were it. Thanks!

  8. Can you please post the pink Congruent triangle page, the congruent triangles with algebra page, and the reference page? I am teaching a Geometry Part 1 and this would be great for them.

  9. Could you please post the pink congruent triangles foldable with the algebra examples? I would LOVE to use it! Thanks!