There have always been stupid ideas around education. Always. Mostly from one of these sources.
1) Highly educated amateurs.
You remember that moment from student teaching. You were about to implement one of those great ideas that you were taught in methods class, and your co-op either explained to you why you should never, ever, do that, or she let you go ahead and try and you went down in flames.
College professors, both in and out of education departments, have always had their pet theories and core ideas that they felt could be implemented in a classroom. That was if they had ever been in a classroom at all, it had been years ago (and research--mine-- suggests that it takes roughly two years to erase every memory of what a classroom had actually been like). So college professors are forever coming up with ideas for the classroom that ought to be right, based on their favorite theories. Sometimes these theories are even "research-based," meaning that they've been tried out on a group of 19-year-old college students being paid to be test subjects, which is of course totally representative of your classroom.
Highly educated amateurs get us everything from management techniques like having low function eleventh graders run a discussion of nature-based symbols in Romantic literature by tossing a rubber ball to each other for speaking privileges, to New Math (best explained here by Tom Lehrer, animation and a bad lip synch, and which may seem vaguely familiar these days).
2) Regular old amateurs.
Everybody in the world has ideas about how to teach The Right Way (frequently best defined as "How I Was Taught"). Traditional grammar and diagramming persist because everybody who ever learned it thinks everybody else ought to.
In low-education communities this often comes up in statements that begin with, "I don't know why you bother teaching..." In high-status communities, it's more commonly "Don't you think the children should be learning about...?"
Sometimes this leads to actual assistance, as in "Your students would probably enjoy doing the double-slit experiment and I just happen to have a mobile quantum physics lab at the house. Why don't I bring it over for you." More often it involves the less possible, as in "Buffy's studies of Shakespeare won't really be complete unless you stage a full performance of Rome & Juliet with her in the lead at Madison Square Garden."
3) Vendors and other snake oil salesmen.
Have you met Collins Writing? If you have, God bless you friend. If you haven't, here's the pitch-- some guy named Collins (I will not give him the benefit of looking up his name) took a bunch of conventional best practices in writing instruction, slapped his own labels on things, added some pointless proprietary rigermarole (have students skip every other line when writing), and marketed it as a "program" to schools for a nice pile of greenbacks.
His ilk have been around forever, but have blossomed in the computer age. If you were in the classroom when computers first arrived, you remember the basic sales pitch from every software vendor;
Vendor: This will be a great piece of software once you change the whole way you teach in your classroom.
Teacher: But what I do now works. I don't see any benefits to my students in changing things to match your software. In fact, I'll get less done.
Vendor: But it's a computer! See!! Computer! Shiny!
4) Private industry.
Public education is where failed management techniques go to die. When a management consultant has finally milked the industrial market dry, there's only one thing left to do-- cover up all those "Management by Objective" stickers with "Teach by Objectives" stickers and hit the school circuit.
So if bad ideas have always been around, why are we so besieged by them now?
Because in the past, we were the gatekeepers of our classrooms. We were the deciders. All of these rivers of crap flowed to our doors, but we were the dam, the filter, and the treatment plant. One of our jobs was to protect our students and their education from dumb ideas.
Oh, we tested them and tried them. Every teacher is, and has always been, a top-notch educational researcher. Every year we collect tons of data and develop a picture of what will and will not work with our students in that classroom.
Reform has been eating away at that, thanks to software salesmen and Texas. Software salesmen learned early on that when making a sale to industry, you don't need to sell to the end user-- you need to sell to the person who makes the purchase (thus, hundreds of engineers working on lousy CAD software purchased by somebody up the chain). And Texas taught textbook creators that if the buyer is the whole state instead of a hundred districts, there's money to be made easily.
Put them together and you get two idea in motion. We need to be able to sell to the boss, and the fewer bosses there are, the more lucrative the deal. So let's set up a system where there's just one boss of everybody and that boss can drive the market. We'll pretty the boss up and make it something harnless-seeming, like a set of national standards for educational awesomeness.
End result of school reform-- we are no longer the gatekeepers of our classrooms. We are no longer the keymasters. Some of greatest frustration teachers are now feeling is the inability to protect our students from bad, stupid, harmful programs. Today's ideas aren't any stupider or more plentiful-- they're just more unavoidable. Bad ideas have achieved great power in the marketplace, and we are increasingly losing the power to stop the sludge from flowing into our classrooms.