Friday, September 24, 2010


I started using Geogebra a little earlier this year.  It is a dynamic Geometry & Algebra software.  I started with Geometer' Sketchpad a few years ago, but recently switched because Geogebra is FREE and can be run on the web (or downloaded).  This way the students have 24/7 access to it. I am the only one in my school using this kind of software.

We started with an intro to look at some of the tools, then we stepped to drawing polygons & measuring their interior and exterior angles and summing them.  Some did not look up the definitions/descriptions of interior & exterior angles, they just assumed "inside & outside".  Some looked them up & even had drawings, yet did not recognize what an exterior angle actually is. I could have told them the "rule" in 5 minutes, but they need to find it. They needed to make this mistake about exterior angles so they actually know what they are.

Students still struggle on computers.  Not just with new software, but basic functions like copy & paste as well as screen capture or using Paint (I thought "everybody knows Paint").  They have trouble with new software programs because they refuse to look through the drop down menus.  They keep wanting me to tell/show them how to do it.  Better yet they want me to do it for them.  One student asked me how to change line size or color for part two, after doing this on the intro practice.  They asked "you want me to remember from something I did before?" And this is a good student.

I use this software because I want them to explore the ideas.  Does every triangle really add up to 180 degrees?  With this software you can draw one, then move a vertex and run through thousands of variations of triangles in a few seconds.  I still get frustrated that students don't know how to use computers for learning opportunities.  I shouldn't because I know they have not had to do these things before.  I really need to keep telling myself "they know nothing about computers."

I had a sophomore girl "fight" me about using computers.  "Math is paper and pencil! We are always on the computers.  I don't need to learn how to do this stuff!  I am going to be a nurse, I don't need computers. I won't need to know how to use Geogebra. If I have to do something on computer they will show me exactly what i need to know."

Oh my.

Sunday, September 19, 2010

Mousetrap cars

Physics classes had to build mousetrap cars that went 7 meters. They were given a board, a mousetrap, some hubs to make CD's into wheels, front wheels, two different size axels and a rod to extend the action arm. I had to pick up some extra mousetraps and found out that they had different diameter windings for the springs. So the metal rod to extend the action arm would not fit inside the coil. Duct tape always works though. The students did a good job of working on the cars and helping each other when they figured out part. It is always a good idea to have a model/example from last year. They did a good job working out the kinks in their cars to reach the 7 meters. They were also supposed to time their car in order to calculate speed (average for both classes, Advanced needed to do instantaneous). As soon as the Advanced heard that 14 meters would get them a grade of 4 (beyond the standard of 3) that was their benchmark. Unfortunately most ignored the idea of timing the car for velocity (tunnel vision on A's). They had to take pictures and/or videotape their cars and write a blog post. I am still waiting for some to get a blog post up and it has been over a week. Overall the project worked well and got them hands on. What Physics did they "actually learn"? Well they were experimenting and revising and troubleshooting. They were also calculating speed.