Our education system.
In OAC chemistry (that's like grade 13) our teacher asked the class what the product of boiling water was. Someone put up their hand and said "Hydrogen gas and Oxygen gas".

The correct answer is water. You know, steam. Water vapour.

So, we put it to a vote. Of 14 people, 13 said that it was hydrogen and oxygen. That means 93% of Ontario high-school chemistry students don't have a clue about change of state, believing that water simply disassociates at rather low temperatures.
(philthemoose asbentee and/or-ed., Fri 7 Jan 2005, 4:32, Reply)