Percent v. percentage points

that MADDENing teacher

Educators may or may not enjoy mining through test data. Generally, though, if data shows an improvement over previous results, there should be a certain level of satisfaction found in processing the numbers. Of course, the converse is true as well.

Despite the results, once the data has been analyzed, it is time to share the information. In doing so, this math teacher has noticed too often the misuse of the word percent.

In the spirit of positivity, let’s say one year Algebra I was at 60% Advanced and Proficient and the next year the scores improved to 75%. We should all agree this is a 15 percentage point improvement.

It becomes a problem when we want to announce to our public a 15 % improvement when in fact it is a 25 % improvement, which, of course, is even better news.

For a quick review on calculating percent of…

View original post 126 more words


About barbarawmadden

I began teaching in 1981, but after a few years decided staying home with my children was what was best for my family. After almost 20 years raising four children, I returned to the classroom in 2005.

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