Most math teachers spend a majority of their time teaching new concepts to their students by demonstrating the correct way to solve problems. There is so much value in teaching math by showing the wrong way to solve a problem and have students work to analyze the errors made.
One of the Common Core Standards for Mathematical Practice is for students to “Construct viable arguments and critique the reasoning of others.” Having students complete error analysis tasks guides students in meeting this standard and developing a stronger understanding of mathematical concepts.
Students view math as following a set of steps or procedures to arrive at the correct answer. Error analysis allows students to critically think about a problem, identify errors and understand how those errors impact the solution to the problem.
Error analysis tasks encourage students to discuss and write about mathematical procedures and concepts. It also gives students the tools to check their own work and identify and correct their own errors. I find that error analysis is a great test prep activity as well.
When creating error analysis tasks, choose “solutions” that contain one or more of the most common mistakes that your students typically make. Allow students to come up with their own erroneous worked out solutions and have classmates correct their work.
Bonus tip: One of the little things I like to do for error analysis tasks is let my students use a “special grading pen” which is usually just a fine tip magic marker! It makes them feel more like the teacher!