Materials
- 4 clear cups or small bowls
- 4 gummy bears (same color/brand if possible)
- Water
- Salt
- Sugar
- Measuring spoon
- Spoon for stirring
- Ruler (optional)
⚠️ Safety Note
After the gummy bears are placed in any liquid, they are no longer safe to eat. As they soak, bacteria can begin to grow. This activity is just for observation—please throw the gummy bears away after the experiment.
Procedure
- Label the cups: “Water,” “Salt Water,” “Sugar Water,” and “No Water.”
- In the “Water” cup, add plain water.
- In the “Salt Water” cup, add water and stir in about 1 tablespoon of salt until dissolved.
- In the “Sugar Water” cup, add water and stir in about 1 tablespoon of sugar until dissolved.
- Leave the “No Water” cup dry—this is your control.
- Place one gummy bear into each cup.
- Leave the bears to soak overnight or for at least 6–8 hours.
- Compare the size and appearance of each bear.
Choose Your Learning Level
Elementary
The gummy bear gets bigger because it soaks up water like a sponge!
Discussion Questions
- What did your gummy bear look like before and after?
- Was it bigger, smaller, or the same?
- What do you think would happen in salty water?
Middle School
Gummy bears grow because water moves into them through a process called osmosis. The bear’s gelatin lets water pass through but not sugar, causing it to swell.
Discussion Questions
- Why does water move into the gummy bear?
- What happens in salt water, and why is it different?
- How could you measure how much the gummy bear grew?
High School
This experiment demonstrates osmosis, the movement of water across a semipermeable membrane from an area of low solute concentration to high. The gelatin matrix in gummy bears acts like a membrane, allowing water to enter due to the concentration gradient.
Discussion Questions
- What is the role of solute concentration in osmosis here?
- Why does the gummy bear shrink in salt water?
- How can you model this process in biological systems (e.g., cells)?