When I taught middle school math, I found that students struggled with simplifying, adding and subtracting polynomials. I used the story below to help students understand how to determine the like terms that can be combined, however my visual learner students still seemed to struggle with the concept, so I came up with the idea of using tiles to represent the monomials within the polynomial so that my students could visually see how the monomials can be combined. My students found that using the tiles made a difficult concept easier to master.
Now that I'm teaching high school, I still use these tiles with students who never "got" this concept in middle school. It usually only takes a couple of practice problems using the tiles and they are able to simplify polynomials on their own without the manipulatives.
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