|Re: 70% of US students don't understand the equal sign|
Message #30 Posted by Crawl on 15 Aug 2010, 12:18 a.m.,
in response to message #29 by bbeamer
Again, the question is ambiguous. There is no established meaning for (), so it's up to the student to guess what the question is asking. Really, the correct interpretation of the results is not "Students don't understand the equals sign" but rather "Students don't understand what the meaningless "()" symbol means ... but why should they?"
I recently saw another study -- was it linked here? -- that ALSO said that students don't understand the equals sign. But the test-makers in that case meant it to mean something completely different! There example was
So now what?
Of course, the answer is supposed to be that now a=b=2, but if you think "equals" always means "you must balance", then those statements made no sense.
In my opinion, teachers often do a very poor job of asking unambiguous questions. One example from my education I remember was when I was asked in an oral example about things traveling backwards in time. I had no idea what was being asked. I ventured, "Are you talking about tachyons?" That seems to me, then as now, to be a reasonable interpretation of the question. Then they rephrased the question, "No, I mean does time have an arrow?" Well, phrased that way, I immediately knew they were talking about entropy. Although in that case, it wasn't so much a question testing my understanding of entropy so much as a test of me having read A Brief History of Time, and knowing that specific phraseology from it.