MAY SOMEONE PLEASE HELP ME, IM CONFUSED The lesson is written for students to graph using
a graphical program such as Graphical Analysis®, Excel®, and similar products. If that option is not available, be sure to provide instruction to the students on the correct way to draw and analyze a line of manual fit:

• Use a straight edge to draw a line in such a way that an equal number of points lie above and below the line of manual fit.

• Develop an equation for this line in y = mx + b format, where y represents the drop height, x is the number of rubber bands, and b is the height of Barbie®. Remember that to calculate the slope of the line, use the equation
Consider dropping Barbie® from a balcony, stadium bleacher, gym bleacher, or band director’s platform. Do not tell the students where the test jump will
be made, only its height. You may want to vary the location from class to class.

The athletic department usually has a very long tape measure that will simplify the measuring task. If a long tape measure is not available, use a long string with a small weight tied to the end. Lower the string to the ground until the weight just touches, mark the length on the string, and then use a meter stick to measure the string. In addition, you may use a motion detector to determine the height of the jump.

An extension of this activity would be to give students the heights in feet and inches so they must apply the factor-label method to successfully convert the given height to meters. Refer students to lessons “Measuring Up” and “Measuring Up, Too” for additional help.

Buy plenty of rubber bands. Two-pound boxes from an office supply store work well. Rubber bands are unique. Most materials when heated expand and when cooled contract; however, rubber bands do just the opposite. If students gather the data inside a warm classroom and then proceed outdoors for the final jump and the temperature is significantly cooler, then the doll will fall a greater distance than predicted.

Be aware that after several uses the rubber bands will permanently deform or stretch, and this may affect the accuracy of the prediction. Let students discover and cope with this complication in any reasonable way. Some of them may consider pre-stretching the rubber bands, replacing the old rubber bands with new ones frequently, or replacing the old rubber bands for the final test jump only.

(Eq. A) • The y-intercept (b) can be found by extending
this line backward until it crosses the y-axis.