Using Snapchat in Math – Applying Similar Triangles


Did you see their face swap?  Did you post it to your story?

Snapchat seems to be the only thing students (and a growing number of adults) worry about most of the day.  Kids are constantly finding creative ways to make funny pictures and send them to friends.  Adults are constantly posting how great their vacation or night on the town is going.  Being the tech-curious person I am, I decided to develop a different way to use it in a math classroom.  Check it out.


Lesson: Applying Similar Triangles

Course: Honors Geometry with mostly freshman and a handful of sophomores

Lesson Objective: Determine the height of the school building using only a ruler and Snapchat.

Standard: ACT CCRS (G 603); CCSS (G.SRT.B.5)

Previous Knowledge: By the time I taught this lesson, we had discussed congruent figures and had discussed that corresponding sides of similar triangles have the same scale factor.  We had also discussed the congruence and similarity theorems.  Students had worked out problems and we more or less comfortable with problems like those below.

SnapChat Pre-lesson

Lesson: Ideally, I wanted to take the students outside to measure the height of the building, but it did not work out for whatever reason.  I ended up giving the students the assignment as an extra credit opportunity and asked them to find the height of their house or some other object that was at least two stories tall.  I handed out the following, then did my best to explain to students what I wanted them to do.  I also created this template for students to organize their thoughts and upload a picture of them in action.

SnapChat Lesson

Results: Here are a few examples of student work.

Sample 1:

SnapChat 1I really liked this student’s work.  They seemed to understand the idea well.  I discussed with them to remember that he started a little below the ground (standing in the street).  Also, note this assignment may encourage to stand in the road for a pose.  Probably not the best…

Student’s Reflection:The only thing that can be improved is maybe try it in class too.”

Sample 2:  

SnapChat 2This student may have understood the general premise, but missed the importance of precision (at least in the drawing).

Student’s Reflection:We probably did it wrong. I thought it was kinda a cool project of how you can find the height of an object outside just by using snapchat and math. What can be improved for next time is showing an example of this project.”

Sample 3:

SnapChat 3We had covered many of those “if John has a 6ft shadow and the tree has a 15ft shadow…” problems and this student – along with others – believed they needed to use shadows to solve the problem.  Unlucky for them, they chose to do the project at sun-down.  Whoops.

Student Reflection: “It was nice to apply the concepts learned in class to real life situations. The most difficult part was trying to find where the shadow actually started and ended. Also, it was a challenge to get the whole picture in one entire frame. Next time, it would be better if we could do this kind of activity in school so that we can verify if we are doing it correctly.”


My Reflections

I really enjoyed the work that I got back from students.  I am curious if this was only a successful application because it was an extra credit assignment for honors students.  Most likely, it would need to be modeled or carefully explained if it was expected for all students of varying abilities to find success with it.

A question I have is whether the lesson could have been more or less effective with less specific direction.  I am a big fan of 3 Act lessons which leads students to ask the questions and determine what information is necessary to solve a problem.  Rather than giving them problems similar to the situation beforehand, could we somehow introduce the situation and have them draw the conclusions by themselves?  Even if we covered similar triangles deeply before the activity, maybe we could let students struggle with how the task could be completed with just Snapchat and a ruler.

Please let me know if you read this and have any suggestions!  I’d love to build it into an even more meaningful lesson for others to use.

p.s. What if snapchat somehow came up with an educational aspect of its application?  That’d be the bees knees.

Not Tech-Savvy? Be Tech-Curious.


The year was 2006.  I was voted most tech-savvy among my friends on Myspace.  To that point in my life, I had mastered the portable CD player and creating a Green Bay Packers themed MySpace page.  I borrowed cell phones to call people and used Ask Jeeves past the point a person probably should have.  I don’t think “tech-savvy” was the correct phrase to describe me.

Fast forward six years to December 2012, my first year of teaching, when I purchased my first smart phone.  A co-worker and I both had new smart phones and we were excited to try these “apps” we heard so much about.  “You should check out this app called Snapchat.  All the kids are using it and it’s kind of fun!”.  Sure enough, it’s awesome, and over the past two years I have developed a lesson for students to learn about similar triangles through the use of Snapchat.

Somewhere around the same time, I began using this thing called Twitter.  You may have heard of it.  My college roommate’s pet tortoise had an account and tweeted about eating lettuce, and my friends used it to share tidbits of our 2012 roadtrip.  Little did I know four short years later I would be using it nearly every day to connect, share, and discover innovative ideas centered around education.  Something happened in the years from 2012 to 2016, and it was great.

I share these stories to show that I really started out on the other end of the “tech-savvy” spectrum.  I grew up with a computer, yes, but compared to my peers, I always seemed to lag a few years behind.  Although I would say I was not very tech-savvy when I entered teaching, I would argue that I quickly became “tech-curious“.  This has led to amazing growth for me as an educator and as a leader.

Being “tech-curious” is an old way of thinking wrapped with a 21st look.  Being tech-curious means that you are realistic about the world in which we live and are determined to find the best ways for students to learn and for peers to improve.

Long before the modern era of iPads, Chromebooks, Smartboards, and apps the best teachers still understood their students.  They understood pop-culture, they understood the most popular styles, and they understood the pulse of each generation; they understood what made their students tick.  Today is no different.  A teacher today understands that smart phones and other technology are part of our students’ lives, and it is our job to find a way meaningful way to bring it into our curriculum, pedagogy, and reflective practices.

I believe being tech-curious is important because using technology effectively offers students more opportunities to collaborate, publish their work, and personalize their learning.  If you are a new teacher or experienced, tech-savvy or not, you have the opportunity to say “YES!” to being tech-curious.”  The change is not instantaneous but curiosity begins to drive who you are as an educator, and you will constantly find yourself tweaking, refining, and asking “is there a better way?”.

Once again, I am labeled one of the “tech-savvy” teachers at my school.  This surely has more value than my 2006 Myspace page, yet I still don’t really feel I have earned the title.  “Savvy” really makes it sound like I have a clue what I’m doing.  Perhaps a title more fitting would be “Likely to try new technology tools, probably screw up, share successes and failures and then annoy people with reminders to tweet their work as well”.

Kind of long winded…perhaps I’ll just go with the title – tech-curious.

Being Proactive with Struggling Students


There has been a growing number of people who have been sharing their “why I teach moment” on twitter.  Maybe you’ve seen them.  I know that I made of one those a while back too, but not remembering what I said before, I would currently say I teach because I enjoy the opportunity it gives me to learn and grow as a human being while allowing me to help others do the same.  It really comes down to helping others improve and be the best they can be.

Personally, I think I nailed the answer to that question.  Yet, in the thick of a day to day struggle “helping others improve” really looks like emails home, silent prayers, and a consistent struggle of getting another human to do ANYTHING productive.  Like seriously, you don’t need to face swap in my class.

Struggle is something that is inevitable in teaching and, when you stop to think about it, is an important part of helping others.  As a teacher, I preach the importance of struggle to my students; using positive strategies to overcome challenges is how I expect them to improve.  Although stressful to the everyday life of a teacher, the struggling students are the ones that push us to be great!

I realized after my first few years of teaching that working with struggling students was something I needed to improve.  With no time to waste, I decided to reach out to my struggling students, but more importantly, their parents.

Before the school year began, I looked up the historical grades of my incoming students.

An easy enough idea but something that was never provided to me at the start of the school year.  Because of this, I knew which students had struggled in previous years before I even met them.  This was good because I knew who may be my struggling learners, but potentially dangerous because now I had preconceived notions of these students as possibly lazy or dangerously unskilled.

I decided to email the parents of any student with a C-, D, or F and set up a conference during the first few weeks of school.

Some of you may be thinking – these are the students with uninvolved parents. Will they even show up?  The answer is YES!  Okay, the majority of emails sent do go unanswered, but when parents of a handful respond, you are given a great opportunity to meet them, get to know more about your students, and set clear expectations from the beginning.

From the meetings, I can tell you that parents are thrilled to see a teacher take the time to really know their son/ daughter from the beginning of the year.  Students, on the other hand, are often aloof because they don’t know if you’re someone that is out to get them or someone who really cares.  Despite a student that appears to be annoyed that a teacher has brought their parent into the mix before the school year even started, you will find as the year progresses you won them over day one.  Showing that you’re more than a teacher that simply goes through the motions to teach students, you win major brownie points.

I try to keep the meeting short – about 20 to 30 minutes.  Here are a few questions/ topics that I like to discuss:

To student (if present):

-tell me about one of your strengths, it doesn’t need to be in school
-why do you say that is a strength?
-how did you get good at it?
-tell me about one of your weaknesses, again it doesn’t need to be in school
-why do you think that is a weakness of yours?
-what do I need to do as a teacher to help you have a successful year?

To parent:

-tell me about your child (parents can run and run with this one, but it all helps paint a picture)
-what have you found your child struggles with in school?
-what strategies do you use at home to help him/ her with learning?

I usually end with a quick mini-lesson on growth mindset and the importance of using the growth mindset language at home and at school.  

Teaming up with the parents won’t mean the year will be perfect, but it does give you a more well-rounded view of the student and sets a positive tone for the start of the year.  I have found success by adding this to my teaching arsenal and hope it could work for you too!