This session is called “Ideas for Using Technology in the Mathematics Classroom” and is presented by Frank Sobierajski.

He’s talking about Geometer’s Sketchpad, which is a piece of software our Hopkins math teachers have been working on since we adopted the Key Curriculum for next year in our secondary schools. He’s showing a quick demo of Sketchpad and how it can be combined with an locus problem activity utilizing a map of downtown Syracuse, NY. The activity combines circules and bisected angles to locate a hidden treasure.

Spreadsheet Sliders take advantage of a feature of MS Excel that allows you to add a custom slider to a spreadsheet worksheet that allows you to manipulate the value in a cell via the slider. It’s in the Tools menu, but I didn’t have time to note exactly where. I’ll leave that as an exercise for the reader. This looks like a good way to control simulations and graphs as the graph updates in real time to reflect the current value of the sliders. One slider can control multiple values because you can create equations that refer to the slider values.

Back to Sketchpad now as Frank shows how to do a similar activity with sliders. The Sketchpad interface is much more elegant than the Excel one, but, of course, not as many people have Sketchpad.

Now he’s using Microsoft Word’s drawing features to build a fractal. It’s too complicated to type here, but it involves repeated grouping and pasting operations.

I’m getting dizzy now as we move back to Sketchpad to work with Sierpinski’s Triangle (never heard of it myself). It’s a triangle similar to Pascal’s triangle that is fairly well known from math classes. We’re looking at more fractals too. The verdict is in. Geometer’s Sketchpad is awesome!

Can you use digital cameras in a math class? Our presenter thinks so. He’s taking a square “STOP” and turning it into an octagon with Sketchpad. Take pictures of interesting shapes and they be imported into Sketchpad for analysis. You can also use a digital camera to do scavenger hunts for shapes like pentagons, slopes greater than one, right angles, parabolas (hint: drinking fountain stream), etc. Another scavenger hunt might include photos of things can come in two, threes, fours, etc. You can also use Sketchpad to plot points on top of images to fit fairly complex functions. Try taking digital photos to study permutations by having students place the objects (maybe a group of their own classmates) in all the possible positions. Video analysis is another area that is ripe for integration with Sketchpad and Excel.

There was way more in this session than I could keep up with. This may have been the best session I’ve ever attended at NECC. The presenter was well-prepared, the talk was well-paced, and the information was so relevant. High marks for Frank Sobierajski.