It’s summer, so hopefully your kids are spending as much time as they can outdoors. As they jump and run around, they’ll no doubt feel their heart beating loudly in their chest. It’s good for their health and—with a little help from you—it’s another learning opportunity, one about their own bodies.

One of our BioBoxes explores the heart, and one of its experiments focuses on heart rate. We use a stethoscope, but monitoring a pulse in the wrist is just as effective for teaching a quick lesson in biology.

Experiment Instructions

Next time they’re playing around, have your kids learn the importance of their changing heart rate:

1. At rest, have your children place their index and middle fingers on the inside of their wrist so that they can feel their pulse. For 30 seconds, have them count the number of pulses. Double that number to calculate their resting heart rate in beats per minute.
2. Have your children do jumping jacks for a full minute, then immediately monitor their pulse for their active heart rate. Measure the rate as you did in Step 1.
3. Repeat Step 2, but instead of monitoring their pulse immediately after the jumping jacks, measure their heart rate after waiting for one minute, three minutes, and five minutes. See how all the heart rates compare. To make things even more interesting, you can use yourself as another test subject.

Draw Conclusions

To help your children draw conclusions, ask a few questions: By how much did their heart rate increase? How long did it take after jumping jacks for the heart to resume its resting rate? Was the heart rate the same for all subjects? There are plenty of questions you can offer for further exploration.

With this simple exercise, you can teach your children about the responsiveness of the heart to physical activity. When muscles need more oxygen under stress, the heart rate increases to deliver it to them. When the body is at rest, there’s less of a need for so much oxygen, and the heart rate can slow down. It’s a simple lesson, but a critical one, and with your children using themselves as test subjects, it’ll be a lesson they’ll remember through experience.

Continuing Learning

Simple lessons are often remembered when they are repeated. Other lessons that are remembered are ones that we do with our hands while using our brains. For more hands-on experiments, delivered monthly, check out the shop page at bioboxlabs.com.