The materials we used were:
Textbooks
12" x 24" ramp
three different mass marbles
standard wood pencil
cm ruler
data collection spreadsheets
groups of 4-5
I asked the question of my students, and then showed them the list of materials. We designed the experiment as a class, while I modeled the experiment in front of the room. This allowed us the time to discuss the change of only one variable at a time. We stacked three textbooks, and we then placed the ramp on the three textbooks. We then placed the pencil perpendicular to the proposed travel of the marble at the bottom of the ramp. To conduct the experiment, the students would roll the marble down the ramp colliding into the pencil. The distance the pencil traveled from the its starting point was measured in cm each time. Students rolled each size marble a minimum of three times to obtain an average. The first variable we chose to change was that of the size of marble used. Students then tested the two other size marbles. After a conclusion was created with regards to the mass of the marble, we changed the slope of the ramp to test a new hypothesis.
The students were able to anticipate the results of the experiment, and hypothesize that the mass of the marble would effect the force of the collision. Students were also able to predict the increase in slopes effect on the collision with the pencil. What went well was the discussion that was happening with the students. I listed different vocabulary words on the board that I expected to hear being used, and students dove right in. The opportunity to discuss with the students the law of conservation of momentum was also valuable since the students now all had the same experience to discuss. The only difficulty I had was getting all of the participating students to see the value in every role. I was given the opportunity to guide students in the art of communication to keep the groups productive.
To create a new design for this experiment, I would like to have students take what we learned from this experiment, and design their own experiment to prove the same scientific concepts. One idea that my students did come up with however was they would like to apply their new knowledge to our sledding hill. We could change the length of the slide, the number of people on a sled, and the different slopes we slide down.
My goal for students to learn in this experiment was the effect mass has on momentum. I think that students were able to grasp the concept based on our class discussion that followed the experiment. We live in big truck country, and students were able to grasp the idea of accidents that might happen between different mass vehicles.
Overall, the experience was valuable.
