EVERYONE at our school knows about the solar car. It's probably the "eco" issue that does it.apparently everyone thinks the solar car is a boat.
We tend to point to visible carbon on the car and say "look! solar panels."
Interestingly enough, there's a civil engg team at our school that makes a concrete toboggan. Never been confused with them however. Maybe that's because they're about as well known around campus as we are...I was asked if it was made out of concrete, because there is apparently a group at our school that makes a concrete boat.