How to Make a DNA Model Out of Toothpicks & Cotton Balls

Make a DNA strand using basic household supplies.

When you are teaching children about genetics and DNA structures inside of the human body, you can make the lesson more interactive by showing the kids how they can make a project related to genetics. For example, use basic household supplies like toothpicks and standard cotton balls to construct a DNA strand. This enables the kids to see what a real DNA strand may look like inside the human body, instead of simply imagining it.

Things You'll Need

• Cotton balls
• 4 lidded jars
• Chalk
• Parmesan grater
• Tacky glue
• Wooden toothpicks

Instructions

1. Divide 24 cotton balls between four different glass jars.

2. Shave a standard-sized piece of colorful chalk into one of the jars. Repeat with a different color of chalk for each glass jar.

3. Place the top onto each jar, and shake each jar to coat the cotton balls with the chalk dust. This effectively colors the delicate cotton balls in four different colors.

4. Squeeze a tiny dollop of tacky glue onto the ends of a wooden toothpick. Push a colored cotton ball onto both ends, selecting two different colors of cotton balls.

5. Squeeze a tiny dollop of tacky glue onto the ends of two more wooden toothpicks. Insert one end of one of the toothpicks vertically into one of the cotton balls in the DNA form. Repeat to insert the other toothpick vertically into the other cotton ball on the DNA form. This completes the first section on the DNA chain.

6. Insert another cotton ball onto the exposed glue-covered ends on the wooden toothpicks. Select two different colors of cotton balls than before.

7. Repeat the entire process until you have glued together all of the cotton balls.

8. Allow the glue to dry for 30 minutes. Hold one end of the DNA model in one hand, and the other end in your other hand. Twist the DNA model in opposite directions half a turn, which will form the structure into a helix formation like actual DNA.

Tips & Warnings

• Keep sharp Parmesan graters out of reach of children.

References

• The University of Maine: Candy DNA Model Lesson