CAS with Unit Rates

CAS with Unit Rates

Mathematics
The Computer Algebra System (CAS) enables students to investigate unit rates, opening up a world of options because the device recognizes words as variables. Teachers can actually enter "one cup of sugar makes two cookies" in fraction form on a TI-Nspire™ CX CAS and get the results shown here.   To promote deep thinking about the topic and engage students in a discussion, ask questions like: Why are these equations true? What stays the same? What changes? What other ratios would work? What other ratios would not work? Asking the right questions is key to starting effective discussions, but what then? Multiple representations help students visually see what the math is doing, which in turn leads to better understanding and skill mastery. Look at the following situation: Joe can mow…
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CAS with Percentages

CAS with Percentages

Mathematics
When I was first introduced to a Computer Algebra System (CAS) device, I thought it was a great tool for my AP Calculus class. The more I used CAS activities the more I realized it would be a great tool for all math students. I believe student investigations are key in deeper understanding of mathematics. CAS devices such as the TI-Nspire™ CX CAS handheld and the TI-Nspire™ CAS App for iPad® give students the opportunity to investigate the why's and how's of math. As I think about important skills for students, percentages stand out to me as an important skill for both elementary and middle school students to learn that is not understood completely. The students memorize the algorithms we set before them but never really reach the mathematical understanding…
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Visualizing 3D Shapes in Algebra

Mathematics
For the past few years I have taught an advanced Algebra 1 course. Some students in this course may have taken Algebra 1 in eighth grade and maybe did not do as well as hoped, while others may have taken Pre-algebra and did extremely well. In any case, these students typically had a good grasp of linear functions; they understood slopes and intercepts and constant rates of change. I was looking for ways to extend these topics and also integrate them with geometry. It was through the 3D graphing features on the TI-Nspire, using the cross-sections of a cube, that we could integrate geometry and algebra and extend their understanding of key concepts. If you have never used the 3D graphing features on the TI-Nspire, I have created a short…
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