Show skydiving video (3:05). Begin a whole group discussion to activate background knowledge on gravity and how it affects the skydivers in the video. Next, students will turn and talk to their groups to discuss why the gravitational pull of earth does not cause the International Space Station to fall out the sky, but it does cause the skydiver to fall to earth. Students will record their answers in their science journals.
Students will use the helicopter template found on slide 4 of the slideshow to create a model helicopter that can be used to demonstrate how the gravitational pull of the Earth affects objects. A PDF file of the helicopter template can be found here. Students will create the helicopters from the template and drop them from a height of 3 feet. In their science journals, the students will record their observations of what happens to the helicopter as it is released.
Using the template, each group of students will create 2 additional helicopters. All 3 helicopters will be dropped at the same time. One from a height of 3 feet, one from 4 feet, and one from 5 feet. Students will time the descent of the helicopters and record the data in their science journals. Repeat 5 times.
Students will use data from this activity to construct an explanation to support their claim that the gravitational force exerted by Earth on objects is directed downward towards the center of Earth.