Have students break into groups of two. Each group will need a land-based, axle-driven vehicle, a piece of cardboard for a sail, glue, rubber bands and masking tape. Students should wear safety goggles during the experiment.
Tell the students that they must attach a piece of cardboard to their vehicle that will serve as a sail. Students may use rubber bands, glue, tape or other materials to connect the sail. Using the Internet or books, each group of students should research land-based vehicles with sails. Have each group sketch its design ideas in the laboratory notebook before attempting the design changes. Once the group has determined the best way to attach the sail, have them complete the design change.
Have students begin the experiment by hypothesizing what effect the sail might have on their vehicle, and how the wind will effect the sail's performance. Ask students to write the hypothesis statement in the lab notebook.
Tell your students to place their vehicles on a flat surface, such as a long table or the floor. Using a fan, have students observe the effect of wind on their sail-equipped vehicle. Have students write down their observations.
Instruct students to write a paragraph about how the sail effected their vehicle's movement. The paragraph should describe whether the sail sped the vehicle up, slowed it down, or changed the movement in any way. Have students compare the results to their original hypothesis.
To further explore the design challenge, have students use a fan with multiple settings to compare the difference in the vehicle's velocity. The groups should hypothesize which fan setting will cause the vehicle to move most quickly. For this activity, have each group lay out a measuring tape along the edge of the flat surface. Have students set the fan on the lowest setting. Using a stopwatch, students should time how long it takes the vehicle to travel the full distance. Students should switch to a medium setting on the fan and measure the time it takes the vehicle to travel the same distance at this setting. Have the group repeat the process with the fastest setting. The group should graph the difference between the vehicle's speed at the three levels. Finally, the group should compare the results to its original hypothesis statement.