Students simulate volcanic lava flows using golden syrup to represent liquid lava. By adding sprinkles (crystals) and marshmallows (rock fragments), they investigate how cooling and crystal formation increase lava’s viscosity and slow its movement.

1. Place a flat board at an angle to act as a slope.
2. Pour about 5 tablespoons of golden syrup into three cups.
3. Leave one cup as plain syrup (runny lava).
4. Mix sprinkles into the second cup (lava with crystals).
5. Mix mini marshmallows into the third cup (lava with rock fragments).
6. At the top of the slope, pour out each mixture. If in a group, pour all three at the same time to race; if alone, pour one at a time and use a timer.
7. Observe which lava flow travels fastest and which moves slowest.
8. Clean up surfaces immediately to avoid sticky spills.

Lava Flow Races - Earth and Solar System:

VISCOSITY RACES investigating the flow of liquids experiment - Kids Fun Science:

📄 Lava Flow Races - Earth and Solar System: https://earthandsolarsystem.wordpress.com/wp-content/uploads/2020/11/lava-flow-races-1.pdf

• Measure the distance and time of each flow to calculate speed.
• Test with different amounts of crystals or marshmallows to see how viscosity changes.
• Use different substances e.g. honey, cooking oil etc.
• Compare flow on slopes with different steepness.
• Add weight (e.g., small objects) to the board to simulate structures in the lava’s path.

• Do not eat any experiment materials.
• Cover surfaces with newspaper, plastic, or do the experiment outside.
• Clean up syrup spills quickly to prevent slipping.
• If outside, be cautious as syrup may attract bees or wasps; those with allergies should observe from a safe distance.
• Dispose of all materials properly and wash hands afterward.

• Which lava flow was fastest? Which was slowest?
• How did crystals and rocks affect the speed of the lava flow?
• Why does increasing viscosity slow down lava?
• What might this experiment suggest about real volcanic lava as it cools?