Using the Crashworthiness Then and Now video as a discrepant event
Since many students do not expect the 1959 Bel Air car to perform poorly in the crash test, this video may be used as a discrepant event. Discrepant events (events that produce puzzling or unexpected outcomes) can stimulate students’ interest and curiosity and help teachers quickly gauge students’ prior knowledge and/or misconceptions. Discrepant events (e.g., demonstrations or videos of real-world events) are typically used at the beginning of lessons to introduce science concepts. And, if they are conducted in an interactive manner that promotes student inquiry and discussion, these learning experiences can also help students improve their scientific habits of mind and critical thinking/problem solving skills. A simple 3-step approach often used in discrepant event inquiry activities is commonly referred to as the P.O.E. method (predict, observe, explain).
Teacher Tips for conducting this P.O.E. (Predict, Observe, Explain) inquiry:
- Before the video, ask students to make predictions about what will happen during the crash test between the 1959 Chevy Bel Air and the 2009 Chevy Malibu. Record their predictions in a column on the board.
- During or immediately after the crash test, ask students to describe what they observe(d) and record their observations in a second column on the board.
- Next, have students compare their actual observations with their initial predictions and identify any discrepancies. If you would like the class to perform more in-depth post-crash observations and analyses, show the IIHS Bel Air and Malibu Crash Data PowerPoint presentation. Present the PowerPoint slides and ask students to compare and contrast the following results/data for each vehicle:
- crashworthiness ratings for each vehicle (Overall rating and performance on each component measured: 1. structure/safety cage, 2. head/neck, 3. chest, 4. right leg/foot, 5. left leg/foot, and 6. restraint/dummy kinematics);
- detailed intrusion and driver injury measurement data for each vehicle;
- ratings of impact forces recorded for the 23 sensors in each vehicle’s crash test dummy.
- Have students investigate the crashworthiness of other vehicles by selecting minicars, small cars, or minivans from the VEHICLE TYPE/SIZE CATEGORY in the RATINGS section of the IIHS webpage. Ask students to scroll to the bottom of the page to find the vehicles that received a POOR crashworthiness rating. Challenge them to carefully observe what happens to each car during its crash test and identify the differences between what happens to the occupant compartments and crash test dummies in vehicles that received a GOOD crashworthiness rating and vehicles that received a POOR rating. Have them try to identify the design elements and safety features of vehicles that received a GOOD crashworthiness rating.
- Have students read "About our tests" to learn more about the six tests the IIHS conducts to determine crashworthiness ratings of vehicles (small overlap frontal crash test, mid-overlap frontal crash test, side impact crash test, rear-impact crash test, roof crush test, and seat belt sled test).
- Conduct the following IIHS in the Classroom hands-on engineering design activities to help students learn more about the science and engineering concepts used to design crashworthy vehicles:
- Egg Crash! Designing a Collision Safety Device
- Paper Car Crash
Ideally, the simpler Egg Crash activity should be completed first since it introduces the key crash science concept of changing momentum through an impulse. This important concept can then be further applied and investigated in the more challenging and dramatic Paper Car Crash activity.
IIHS Bel Air and Malibu Crash Data PowerPoint presentation