In the course of our human body unit, we have just wrapped up the nervous system. Part of the discussions included how our brain can send and receive messages to other parts of the body through neurons. Sometimes, these messages are sent almost immediately, without us really thinking about the process (think about when you touch a hot stove!). Other times, our brains take a little longer to process what needs to be done.

To demonstrate this point, the class did a quick reaction time lab. I first found this lab at TheHomeschoolScientist.com and I’m so glad I did! It was a blast!

For the lab, all you will need is a ruler or meter stick, and a conversion chart like this one:Image result for reaction time table If you don’t have a conversion chart ready, simply use the inch marks as your indicator!

You can get the entire lab and worksheets for free by visiting TheHomeschoolScientist.com and signing up!

Round 1

  1. The student being tested holds their hand out, ready to catch the ruler.
  2. Another person in the group holds the ruler with the end of the ruler (the “zero” inch mark) right above the blindfolded person’s thumb
  3. The person holding the ruler will drop the ruler without warning, and the student being tested must grab the ruler as quickly as possible.
  4. Check what inch mark the top of the student’s thumb is resting on.
  5. Record the number, then use the conversion chart to see the reaction time (if using the conversion chart)
  6. Repeat this process two more times. Students then find the average of all three trials.

Students had a great time watching each other try to catch the ruler as quickly as possible!  

If your students seem ready for the next challenge, gather several blindfolds and have students test their reaction time in a slightly different way!  

Round 2:

  1. One person in the group is blindfolded and holds their hand ready to grab the ruler
  2. Another person holds the ruler with the 0 inch mark right above the blindfolded person’s thumb
  3. The person holding the ruler counts, “1, 2, 3, Go!” and drops the ruler on “Go”
  4. The blindfolded student listens for “Go” and grabs the ruler.
  5. Another group member takes note of how far down the ruler went and sees at what measure the student’s thumb is near and record the time using the chart.
  6. Repeat this process two more times. Students then find the average of all three trials.

**If you do not have anything to use as a blindfold, just have students put their heads down on their desks and close their eyes. This can be way easier than messing with making the blindfolds just right around kids’ heads.**

Follow up questions to ask students:

  1. Which method did you have the quickest reaction time?
  2. Was this the better method for everyone in your group? Explain.
  3. Why might some people’s reaction time be faster than others?
  4. What errors may have occurred that would affect the outcome of this experiment?

Leave a Reply

Your email address will not be published. Required fields are marked *

Comment *






This site uses Akismet to reduce spam. Learn how your comment data is processed.