How Standardized Testing is Killing American Education: Reason #8

Third in a series.

8) "Scaled scores" don't tell you anything about student learning: Standardized tests scores are given as "scaled scores." This means that your score is not based directly on how many questions you got right: a student who answered 25% of the questions correctly would not receive a score half that of a student who answered 50% of the questions correctly. Rather, the scores tell you how many other students that took the test scored worse than you did. A student who scores in the 35th percentile did not necessarily get 35% of the questions correct. What happened is that 35% of the students who took the same test got less questions correct than that student did. It's possible that they got 35% of the questions correct, but it's just as possible that they got 5% of the questions correct, or 75%, or even 90%. A scaled score doesn't tell us anything about the number of questions answered correctly.
Likewise, improvement on a scaled score doesn't necessarily indicate improvement in learning. A student could answer 45% of the questions correctly one year and 55% the next year. Their scaled score could improve, or drop, or stay the same, depending on whether other students improved similarly or not. Ideally, we want all students to improve, don't we? Well, if that happens at the same rate, our scaled scores will not change at all, and will give no indication that the outcome we most desire is actually taking place!
Scaled scores are deceptive on several counts. First of all, it is not uncommon for someone to think that someone with a scaled score under 50% has mastered less than 50% of the material. That is not true. Someone with a scaled score of 50% scored higher than 50% of the students who took the same test. In other words, this is a totally average student. Right in the middle. Typical of American students in general. This students actual score could tell us a lot about the state of American education: if an average student has an actual score of 20%, we would be disappointed; likewise, an "average" actual score of 85% would be very encouraging. Unfortunately, the only score we're ever exposed to is the scaled score, which doesn't tell us a lot about what (or whether) students are actually learning.

(Resources: 1 2)

-"USA Today has come out with a new survey: Apparently three out of four people make up 75 percent of the population."