You may say we can get good physics and "good" math, but that just ain't true any more - especially for lower level classes. It is for that reason that I introduce my students to the first cousins of cross-multiplication.
I interviewed a chemistry teacher and a physics teacher in the following video to bring out the algebra weaknesses our students have. Then I presented what I call "cross-switching" and "cross-moving."
Cross-multiplication is just a name for two multiplications in one step. Cross-switching and cross-moving hang on the same principle using multiplication and division.
I expected protests and quickly confronted some from a math teacher next door. He expressed his discomfort with my proposed techniques from what he called a "math purist" perspective, stating that he would not teach those techniques to his math students.
He then quietly confided that he uses my approach on a regular basis in his own brain. Other teachers have said the same. They use easy algebra daily that they refuse to teach their students. I have also felt constrained to use the math I "should" use but I have recently decided to abandon anything that makes the physics more difficult.
Many math teachers despise cross-multiplication, calling it a "tomfoolery," "wizardry," or a "trick." Whatever. I'll have my students use cross-switching and cross-moving every day - it's better for Fzx.
No comments:
Post a Comment