Geoboard app and other items.

In geometry, I passed out a worksheet that has the students physically draw a quadrilateral, pentagon, hexagon, etc  and then draw line segments out form one vertex to others to create triangles inside the figure. Today, I took the same worksheet and had the students do this on the Geoboard app.  My high schoolers really had a great time working on this. They did get a bit frustrated when they got to 7, 8 or 9 sides however no one rushed to finish this.  On Monday, I am going to have the students add a chart to the back of  the paper for total degrees, each interior angle and a column for exterior angles, the number and their measure.  We will be using the Geoboard app and this way I hope they have as much finding the answer to the questions for each shape that they still have to answer.  Most of the questions deal with the idea that if you change the size of the figure, the number of triangles will not change.
Today I showed the students the yahoo video about the college aged girl who ended up being charged a total of 787.33 for her cab ride of 2 miles.  Then they answered three math questions such as how much was she charged per miles, how much was the tip and What is your opinion of the whole event.  They have requested I provide more of these types of warm-ups.  This is great that I've got their interest.

Found app for use with polygons

I found a lite version of the Sum of Exterior Angles which helps students explore that all the exterior angles add up to 360 degrees always.  This might be a nice way to help students learn the material  but I am also wondering if we could accomplish the same thing using one of the apps I already have on the iPad.
I know I can use the geoboard to help students constructively learn that the total interior angles is based on the number of triangles you can subdivide the figure into.  I am wondering if I extended the side further out so that students could see that the exterior angle.  On the other hand, the Sum of Exterior Angles lite allows students to explore this concept using both regular and nonregular polygons.  Maybe I will just download it and see how it actually works.