Back in 2010, Dan Meyer linked to a delightful article about how the price of gasoline is actually cheap when compared to other liquids.
This leads to the obvious question: how much would it cost to fill our car up with liquids other than gas? And it’s a beautiful example of how getting ridiculous leads to some really interesting thinking — and highly engaged students.
Here’s what I ended up doing with this inspiration:
- First, I had students buy a car. They can use Carmax or any car maker’s website to pick the vehicle of their dreams. Why? So we can get the size of a real gas tank. Plus, it’s fun and they’ll probably learn something random along the way. At this point, everyone should have their fuel tank capacity.
- Next, we shop for gas. There are many ways to do this, but we want an average price per gallon for gasoline in your area. GasBuddy.com is one option.
- With this information, students calculate the cost to fill their tank with gasoline.
- Now, we search for the price of other liquids. Kids will tend to fixate on beverages, so perhaps limit them to only one typical drink (soda, orange juice, milk, etc). Move them towards other ideas: detergent, perfume, olive oil, motor oil, or clam chowder. Take a lot of time here to get some off-the-wall, unusual ideas. It makes this all way more fun.
- Finally, we calculate how much it would cost to fill up our car using those three liquids. Is gas really that expensive? (Not if your car ran on printer ink!).
In the end, students could share their findings in any way you’d like: presentation, skit, public service announcement, persuasive essay, you name it!