The HOW and WHY Behind Standard Deviation

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Students will be able to build on their entry level knowledge of standard deviation and extend it to their maze data set in a previous lesson.

Big Idea

This lesson works to give the teacher the flexibility to “paint” his or her own description of standard deviation, while providing the basic flow and context of the lesson.

Entry Question

6 minutes

As the students enter, I have the opening PowerPoint slide pulled up which prompts them to reflect on the connection between data collection, the particular type of study, and the bell curve.  The student responses are linked to a question.  This question does not have a “right” answer, and allows the students to respond to a variety of perspectives.  Using ensures that all students feel safe responding to the opening question, regardless of their ability level.  Out of your classes sample size, you will be sure to get a great deal of discussion points that not only connect to prior learning, but also help to motivate the day’s lesson.

Lesson Middle: Standard Deviation

20 minutes

Calculating the Standard Deviation for our Maze Data

20 minutes

To conclude the day’s lesson, I help the students find the standard deviation of the data set that we used for our Maze lesson.  Typically, I plan to do either the boys or girls data as an example, and then allow the students to find the other one.  This is a really challenging lesson for the students to this point, and they may continue to need support understanding exactly what the standard deviation is.  I HIGHLY ENCOURAGE my students to come and see me during homeroom or before school if they would like to see it re-explained in a new way.  I tell the students that as long as they are persistent, it will make sense eventually!  It is important to me that they understand the how and why behind standard deviation, otherwise, it is nothing more than calculator work! 

I save an additional practice problems with standard deviation for later lessons because I want the students to focus on the concepts – I am trying to avoid the “just a teach me how to do it so that I can plug and chug” approach to learning.