NOT BASEBALL

I spent some time this week browsing conference proceedings from ICTCM and AMATYC to try to find something to learn.  As usual some of the sessions posted were things I already knew.  Other sessions were things I didn’t want to learn.  One that caught my attention was Workshop 14 at AMATYC’s 2009 conference.  Rob Kimball presented It Is a Sure Bet. The Appropriate Use of Technology Deepens Understanding.  (The link opens a spreadsheet).

Kimball’s session showed how to use spreadsheets in algebra classes at various levels.  This is not surprising because he also led a reform project to find real-world problems in College Algebra called The Right Stuff.

I already knew how to do many things he does in this spreadsheet.  For instance I have used sliders.  Still, it is good to know that if I ever need a refresher on how to create sliders you can find it here.  Kimball also has a creative version of the problem that is usually set up as delivery of utilities to a manufacturing plant or city on the other side of a river.  In the traditional problem overland cables cost less to run than underwater cables,  His set up instead involves creating an irrigation system on a large farm.

One simulation lets you vary the number of dice you use.  To do this a simple if statement is used to turn on or turn off dice depending on a users preference.  I also learned about the countif statement.  Kimball uses this to count the number of virtual dice showing sixes.  “=COUNTIF(C5:Y5,6)”  I will have to explore whether countif can be also used with inequalities.

One of the most interesting things that I had not thought about was putting a picture on the background of a graph.  Then by using sliders to move points you could find the slope of a line in the picture.  Or you could confirm that a shape could be fit with a quadratic.  Kimball uses the Luxor hotel for the slope and the Hoover dam for the quadratic.  

Kimball’s session’s Excel file is worth a look.  Excel experts might- like me- have one of those “Oh duh” moments.  Mine was realizing that you could make a real-world example just by dropping a picture behind your graph.  Kimball steps through some examples and has a couple exercises with solutions so novices can probably gain something, too.