I used the string from the Science Kit, along with a paper clip, a pencil, pennies, and some masking tape. I was trying to determine what variable would change the number of swings in 15 seconds. My first scientific question was “Does the weight affect the number of swings?” In this experiment, I used a string that was 38 cm from the end of a loop to the end of the paper clip. I taped a pencil down to the counter and hung my pendulum loop over the eraser so it had an obstacle free place to swing. I set the kitchen timer for 15 seconds and decided the period would be from the point of release (top of the counter) back to the original point of release. The independent variable I was changing was the mass of the weight. I used 1 penny and 3 pennies, securely fastened in the paper clip. I started with one penny in the paperclip and in 15 seconds, recorded 12 swings. Then I put three pennies in the paperclip and in 15 seconds recorded 12 swings. My conclusion was that the mass of the weight really did not increase or decrease the number of swings.
Next, I made a list of the other independent variables I could test to determine what affected the number of swings. I concluded that the length of the string, height of the string, amount of tape, and force of release could all possibly play a role in the number of swings. For the next experiment, I altered the length of the string. My hypothesis was that if I increase the length of the string, then the number of swings would decrease. I made a 4 more pendulums the exact same way measuring from the end of the loop to the tip of the paperclip. I used one that was 20 cm, 60 cm, and 100 cm. I did one pendulum swing at a time and recorded the number of swings in 15 seconds. For 20 cm, I had 15 swings. With 60 cm and 100 cm, I had 9 and 7 swings respectively. My conclusion was that as the length of the pendulum increased, the number of swings decreased.
The best part of this guided inquiry experiment is that the students will have control of the experiment. The students would get to work collaboratively with others using simple, accessible and cheap materials. Due to the fact that I do not teach motion and force in my standards, I would use this lab to teach about the scientific method. There are so many teachable moments a teacher could use during an inquiry activity like this; for example, controlled variables, manipulating variables, graphing, making data tables, making hypotheses, doing many trials, and taking averages. The challenge of this experiment would be for the teacher to stress to students that the experiment must be controlled. Each group can only manipulate and test one variable. Other than that, this experiment is a wonderful, quick, easy, and affordable way to add inquiry to your classroom to get your students thinking.