So on Twitter.com/dmarain this morning I posted the following (I modified it slightly):
"Java Coffee Co." gives you a free cup after you purchase 12. The % discount is 7.7% rounded.
Wonderful concise conceptual explanation from @MrLeiss on Twitter this morning. This is what sharing of ideas is all about!
See it on my account at
So where's the formula for % discount? % change in general? Why is it NOT in that video? Uh, that's rhetorical...
As I explained in my video --
THIS IS NOT INTENDED TO BE PRESCRIPTIVE OR SCRIPTED!
It is just one old retired math teacher's way of keeping the dialog going and we all know that sharing of ideas is the only way our students will understand math better. We do believe that, yes??
SO SHARE YOUR THOUGHTS BUT PLS REMEMBER THE RAISON D'ETRE OF THIS BLOG. THE PROBLEM AND THE "ANSWER" IS FAR LESS IMPORTANT THAN THE METHODS WE USE TO DEVELOP CONCEPTUAL UNDERSTANDING.
My Core Beliefs
1. THERE IS NO ONE BEST WAY TO TEACH THIS!
2. BELIEF #1, NOTWITHSTANDING, SOME WAYS ARE BETTER THAN OTHERS.
3. IT IS NEVER TOO EARLY IN A CHILD'S DEVELOPMENT TO INTRODUCE MATH CONCEPTS. IT'S JUST A MATTER OF HOW WE SAY IT AND HOW WE SHOW IT AND HOW WE ASK THE QUESTIONS AND WHAT ACTIONS WE ASK THEM TO TAKE!
4. CONCRETE (PHYSICAL OBJECTS) TO SYMBOLIC TO ABSTRACT ALWAYS MAKES SENSE REGARDLESS OF STUDENT DEVELOPMENT.
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