I'll have to disagree with you a bit on what you said. Scientific literacy is very very important, and I think the world would be a much better place if people where, in general, more scientifically literate (no more global-warming deniers, eh, americans?). However, I feel like one does not have to have the understanding that an undergraduate has of a field to be scientifically literate in that field, nor does a person need to have all the correct terminology.

In my opinion, all that is needed is a general change the people's spirits regarding their thinking. People, in general, lack critical and scientific thinking. What I think could help is an "addon" to education that focused on the scientific way of thinking: of accepting new ideas, and of testing them, and of seeing the results for your won eyes instead of taking other's words for it. In my mind, if people in general and a little bit more of critical thinking and of scientific reasoning the world would be a better place, and everyone would be happier. I don't need (nor want) everyone to have an amazing understanding of a ton of scientific fields, all I want is for people to have an open and critical spirit capable of changing their ideas and beliefs when confronted with new information.