
Walk the Graph
Caroline Woodason
8th grade
North Whitfield Middle School
Whitfield County Schools
Task

Overview
In this task, students will use CBR™ motion detectors to create realtime graphs displaying lines with positive, negative, and zero slopes.
Illustrative Task
Eddie’s teacher used a motion detector hooked to an overhead graphing calculator to show graphs of how far Eddie was from the motion detector for a few seconds. Eddie was asked to walk in such a way as to produce graphs with certain characteristics. Explain how Eddie needs to walk to produce a graph which is:
 A line with a negative slope.
 A line with a positive slope.
 A line with a steeper slope than the one in part (2).
 A horizontal line.
 Not a line.


GPS Addressed

M8A4. Students will graph and analyze graphs of linear equations and inequalities.
a. Interpret slope as a rate of change.
b. Determine the meaning of the slope and yintercept in a given situation.
c. Graph equations of the form y = mx + b.
d. Graph equations of the form ax + by = c.
f. Determine the equation of a line given a graph, numerical information that defines the line or a context involving a linear relationship.
g. Solve problems involving linear relationships.
M8D4. Students will organize, interpret, and make inferences from statistical data.
a. Gather data that can be modeled with a linear function.
b. Estimate and determine a line of best fit from a scatter plot.


Video Information


Use these questions to guide your thinking about some of the important teacher ideas in the lesson featured in the video clip.
 What kinds of questions does the teacher ask to promote students’ problem solving?
 How is the teacher gauging students’ current understandings and building from those understandings?
 Consider the GPS standards listed with this video.
 What makes this lesson different from lessons you have taught on this topic?


