Ms. Kahn and her class became interested in how U.S. soldiers are trained. The U.S. military is one of the most highly trained militaries in the world. An elite Army unit called Army Rangers conducts special missions, like helping to displace enemy regimes in Panama, Iraq, and Somalia. The Rangers’ nine-week intense training prepares them to lead a group of soldiers even while working in unstable, unpredictable, and physically challenging situations. They get an estimated 3.5 hours of sleep and eat two meals or less each day during training sessions.

Raj asks, “Wouldn’t lack of sleep and hunger cause slower reaction times?”

Ms. Kahn responds, “I doubt the intense training would diminish the quick-thinking skills of these elite members of the service. But we could test to see if our reaction times might be affected!”

Raj enjoys setting up experiments, so he set up an experiment that would help find an answer to his question.

Question: Does hunger affect reaction time?

Hypothesis: Students have better reaction times when they are not hungry. Materials: 30 cm ruler.

Procedure:

1. Set up testing sessions with test subjects right before lunch and right after lunch.

2. Have the subjects hold their fingers and thumb at the zero mark of the ruler without actually touching it.

3. Let go of the ruler without warning and see how quickly they can catch it as it falls.

4. Record the centimeter mark where each subject caught the ruler.

5. Repeat same test after lunch.

Discussion Question:

Have a class discussion about how seriously Raj should take his concerns. Do you have advice for Raj about a way he could improve his experiment?