This activity has two goals. First, to demonstrate the idea of a force that causes negative acceleration, also known as deceleration or slowing down. The second purpose was to model the concept of how to do a data chart with numbers, and how to graph numeric data. My children's response startled me.
The set up calls for markers, arranged in a line, and a toy car. I rolled the car into the row of markers slowly, so that only one marker fell down. It took one marker to stop a slow car.
On my data sheet I wrote "slow and "1". Next I rolled the car at a medium speed, about what I expected to knock down half of the markers. It took three markers to stop a car from medium speed. I wrote "medium" and "3". on my data sheet. I repeated with a fast car.
Next, I hand drew a simple graph representing my data. I thought that was the end of the lesson. My intention was to have my kids apply these skills on our final experiment. I set them free to enjoy knocking down the markers with the car.
A few minutes later my graph had new data.
A few minutes more passed, and I was asked to assist in numbering this master piece.
Real data tables and graphs are done either freehand, or later, on computer. After seeing my children's enthusiastic response, I am convinced that this is a better way to introduce graphing than through graphing on a pre-done graph. My final experiment does use a pre-fabricated graph, and my children compliantly followed directions, and where then happy to move on.
This combination of demonstrating the experiment, with data table and graph, then setting my children free to re-create what I had done worked astonishingly well. I would love to see how it would work in a standard classroom. Would you use it as a station activity? If anyone has the class and the will to try it, please let me know how it goes!
This lesson is part of my new unit Toy Car Physics! Click here to check out the other activities.