A very common science project for young kids is making a volcano out of cardboard and using baking soda to make it erupt.
But what is this teaching the kids? And in what way is it science?
This is NOT how a real volcano erupts. It does not model a real volcano in any way. It does not demonstrate any geology or siesmology. It does not use the scientific method to investigate anything. It seems to me that this is just an art project. Why do so many teachers allow it to be called "science"?
I’ve seen this demonstration and the Mentos in the soda bottle used just to provide a visual effect without any explanation of the science behind it. I agree with you that this project can be just an entertaining display and doesn’t really help kids understand science – if its not done right.
If set up properly though, then it does demonstrate science.
Volcanoes erupt because of expanding gases within the magma. The CO2 bubbles mimic that by forcing the material up and out of the vent. This is both chemistry and physics in action.
The material that is "erupted" flows down slope under the influence of gravity, and if the volcano model has any depressions in it, it can show how fluids (molten rock) follow the path of least resistance. When the material reaches a horizontal surface the flow will slow and eventually stop, like a lava flow would. This can also be used to demonstrate how streams deposit sediments when their gradients shallow.
Its a model and therefore is a useful tool for students to make predictions and experiment with. There are plenty of "what if" questions that can be asked before, during, and after that help the students get to the meat of the topic.
I’ve seen models where small towns are drawn at the base of the volcano. Students could be asked about land use decisions, hazards, and other issues related to living next to or on a volcano.
All in all, it can be a useful tool, but like any other tool, if not used properly then its just a waste of both time and materials.
It’s just a simple fun chemical reaction, no it doesn’t show how a real volcano works but for someone young it is very exciting.
References :
I’ve seen this demonstration and the Mentos in the soda bottle used just to provide a visual effect without any explanation of the science behind it. I agree with you that this project can be just an entertaining display and doesn’t really help kids understand science – if its not done right.
If set up properly though, then it does demonstrate science.
Volcanoes erupt because of expanding gases within the magma. The CO2 bubbles mimic that by forcing the material up and out of the vent. This is both chemistry and physics in action.
The material that is "erupted" flows down slope under the influence of gravity, and if the volcano model has any depressions in it, it can show how fluids (molten rock) follow the path of least resistance. When the material reaches a horizontal surface the flow will slow and eventually stop, like a lava flow would. This can also be used to demonstrate how streams deposit sediments when their gradients shallow.
Its a model and therefore is a useful tool for students to make predictions and experiment with. There are plenty of "what if" questions that can be asked before, during, and after that help the students get to the meat of the topic.
I’ve seen models where small towns are drawn at the base of the volcano. Students could be asked about land use decisions, hazards, and other issues related to living next to or on a volcano.
All in all, it can be a useful tool, but like any other tool, if not used properly then its just a waste of both time and materials.
References :