What are the most successful experiments and activities to do with students when covering the human body?
— K., West Virginia

Here are a few of my favorite demonstrations and activities. Look online or in the NSTA Learning Center for most of these.

Digestive System:

• Peristalsis demonstration: Stand on your head and drink juice/water through a straw.
• Stomach gurgling: Simulate how peristalsis pushes air through your digestive system when you haven’t eaten. Hold 1.5-2 meters of garden hose by both ends to form a “U.” Pour in 100 ml of water and blow into one end.
• Digestion: Soda cracker pie tastes exactly like apple pie but is made with starchy crackers. Cooking breaks starches down into sugars just like amylase enzymes. This could be a great treat on a Friday, but be aware of any food allergies or sensitivities your students may have.
• The Great Digestive System Time Trials: Students voluntarily eat small bowls of cooked corn. They anonymously report—in a note, on a wiki, or in shared spreadsheet—how long it took for the corn to…uh…reappear in a bowel movement.

Nervous System:

• Onion/apple tasting: Students can design an experiment to check out how smell and taste affect each other.
• Color blindness tests: Students are riveted and cannot believe the range of color vision evident in just one classroom. Three of my students discovered that they were color blind!
• Two-point discrimination of touch: Two toothpicks glued at different distances apart on cards are gently touched to the skin to map the sensitivity of hands, feet, arms, and so on.

Circulatory System:

• Blood pressure and heart rate experiments: Pairs of students design experiments on factors affecting blood pressure or pulse. Stay away from the typical “fit vs. unfit subjects” or “the effect of running on pulse.”

Hope this helps!

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