Harold Jacob's excellent Mathematics: A Human Endeavor introduces several mathematical ideas via the game of billiards. I suspect his text is the inspiration for the NCTM Illuminations's Paper Pool lesson plans. Although the Illuminations site provides a Java applet, I … Continue reading

# Tag Archives: algebra

Most of the functions we look at in high school math are continuous everywhere they are defined. But not always. Graphing piecewise functions with software requires defining the function on distinct intervals. Grapher (on the Mac) provides a nice facility … Continue reading

Factoring numbers is something kids learn early in school. Creating a factor tree is the standard device for generating the prime factorization of a number, and the prime factorization paves the way to many mathematical ideas. I've found my students … Continue reading

We make lots of graphs. Sometimes I embed the graphs in the handout. But other times, such as for creating graphs that will be cut out and attached to a group chart, a separate piece of graph paper is better. … Continue reading

I use the Addition and Subtraction slide rule to give students an experiential manipulative that represents what happens when we add and subtract integers. I was trying to come up with something similar for multiplication and division. I had a … Continue reading

Math is not real. But we use math to model reality. A commonly used model is the linear model, a kind of function. A function has the property that, given a number as input, it produces another number as output. … Continue reading

Here are some convenient number line graphics you can print or insert into your own documents. Wall poster from -15 to 15, to be printed on 31 sheets of 8.5x11. -15 to 15 in PNG format -15 to 15 in … Continue reading

The spreadsheets below contain randomly generated practice questions. To generate a new practice sheet on a Mac, type command-shift-=; on Windows, press F9. Single digit integer addition and subtraction practice spreadsheet. Single digit integer multiplication practice spreadsheet. Single digit integer … Continue reading