GeoGebra is amazing and in less than 72 hours it has changed my teaching forever.

What is GeoGebra? Its amazing. Have I mentioned that? It is an open-source piece of software that aids in constructing geometric figures and visualizing functions.

That was a lame description. It is so powerful and I have not done it justice. What you really should do is go here to see some tutorials. Check out this one, its my favorite so far.

**How did I get here?**

Like most teachers I know, I keep a “teaching to-do list.” What follows is a sampling of that list:

- Write letter of Rec. for Joe.
- Get vertical alignment documents from AP website for collaboration
- Move to GeoGebra

This last item on the list, “Move to GeoGebra” is new. It replaced, “Figure out how to use Sketchpad with Algebra/PC/BC.” Sketchpad is a reference to the amazing software called The Geometer’s Sketchpad. This software has been around for a very long time and it is insanely powerful. I finally found time this week to build an investigation in my classroom where students would be using Sketchpad. It was so much fun. I created a tutorial for my calculus students. It showed them how to use Sketchpad to build a tangent line. I then tasked them with the challenge of using these newly aquired skills to build a Newton’s Method Approximation in Sketchpad.

This was awesome because they had just the day before seen a demonstration of how Newton’s Method worked but had not yet been asked to formalize the idea. So, they were learning new software and trying to make it do something they were not confident with yet. It was messy and beautiful.

That brings us to yesterday.

**GeoGebra > Sketchpad**

Today, I decided that I really needed to start playing with GeoGebra instead of Sketchpad simply because I cannot get copies of Sketchpad for each of my students (a student version is $35).

GeoGebra is free. Did I mention that? This is a big deal and its **the** reason why I am now a GeoGebra user.

Thanks Sketchpad, you got me excited about visualizing math in a meaningful way but I can’t afford you. If you were to give away copies to students for free then maybe we could keep seeing each other.

As I began to experiment with GeoGebra this morning I found it did everything I needed it to do. I am certain that there are features in Sketchpad that are notably absent in GeoGebra, but GeoGebra is free. Did I mention that? Also, its awesome.

The interface in GeoGebra is very different than Sketchpad and it was a bit daunting to me at first. Though I am happy to report that after less than an hour with two tutorials (as mentioned above) I found it far **more** intuitive and user-friendly than Sketchpad.

**What’s next?**

I am searching for ways to use GeoGebra in two different “modes.” My end goal is to put this in students’ hands as quickly and often as possible. If I can convince them that this tool is as helpful as I think it is, then they will access it on their own I’m sure.

In order to give my students opportunities to explore math with GeoGebra, I need to become an expert in it quickly. So in order to facilitate “student” mode I need to work hard on “teacher” mode.

Today, I began to explore how I could use GeoGebra to show the two linear functions my student teacher was discussing with our Algebra class. I found I could very quickly produce a display that would demonstrate the ideas he was presenting in handwritten form on the whiteboard in a much more dynamic and convincing way (were I to show this to the whole class).

My brain is still kinda exploding right now. I can see how many things are possible with this tool and I genuinely regret never making this a priority before. This could have changed my teaching long ago, had I moved it up the list from the bottom. I never really seem to get around to the stuff at the bottom.

**That’s not exactly true**

Luck doesn’t explain why I am now playing with this software. Its not coincidence that I finally managed to make it down to an item at the bottom of my list. There were a series of things/events/experiences that occurred first and I believe prepared me for this step.

1. A colleague shared his GeoGebra experiments with me.

He sent me the files, the tutorials and his excitement about how helpful it was for his students in making meaning out of their learning.

2. Our math department finally got our own mobile laptop carts and a site license of Sketchpad.

3. I made a commitment to trying new things again.

**Stay tuned**

I hope to post more specifics about what we are trying, so stay tuned.