For instance there is the issue of global warming. I think it's fair to say that the single point being taught in school is that global warming is caused by greenhouse gases and "your parents are killing the planet and will leave you nothing more than a barren ball of rock".
Obviously that's not the only hypothesis and there are probably some honest scientists that believe it. On the other hand I think it would be inaccurate to say that there are some in the global warming camp that are in fact dishonest and totally agenda driven. It (global warming) has become a political movement.
Perhaps unfair but science was once known entirely for critical thinking. To at least some of the unwashed masses (of which I include myself) science is now seen as often as not as a pure agenda operation and facts be damned. Fair or unfair the whole area of science is tarred, especially when whackjob science is defended as "an open and frank exchange of ideas" or whatever the ivy tower says when a professor or researcher goes off the deep end.
Like Muslims needing to speak out against terrorism science needs to speak out on junk science. Alas it appears that grants, funding and the like preclude that but regardless in my opinion science needs to do that to regain some credibility with the rest of us.
The website Junkscience.com is a useful corrective. Michael Fumento is an excellent science writer who spends a lot of time debunking an amazing amount of nonsense, and his webite, www.fumento.com, is outstanding. (He posts his hatemail, which is always good for a laugh).
Regarding the past, the junk was always out there, it's just that the nonsense has been forgotten for the most part. If you're really interested, I can Freepmail you a reading list.