Error Analysis

Lucy and Ethyl were analyzing the linear relationship represented in is table below. Lucy said the unit rate of change was 2.  Ethyl said it was -½. Convince Ethyl why she is incorrect and why Lucy is on the right track.


Error analysis activities have been shown to be very helpful for students to confront misunderstandings and clarify their thinking.  In particular, they

Promote higher level thinking.  

According to Robert Marzano, error analysis is at the top of higher level thinking skills.  It requires students to create, analyze, and even prove their claim.

Aid in conceptual understanding.  

The tricky part of having students do traditional algorithms is they sometimes lose the conceptual reasoning behind the steps.  When students can find errors in a process and explain it (that part is key), they are really showing a conceptual understanding of the skill or concept

Rather than warning our students about errors to avoid, we can use errors as catalysts for learning by approaching errors as problem-solving situations. For example, a group of students can examine an erroneous procedure and use reasoning with concepts they know to determine why the strategy that was used does not always produce a correct answer.