It's always hard to tell for sure exactly when a revolution starts. Is it when a few discontented people gather in a room to discuss how the ruling regime might be opposed? Is it when first shots are fired? When a critical mass forms and the opposition acquires sufficient weight to have a chance of prevailing? I'm not an expert on revolutions, but even I can see that a new one is taking shape in American K-12 public education.
The dominant regime for the past decade or more has been what is sometimes called accountability-based reform or, by many of its critics, "corporate education reform." The reforms consist of various initiatives aimed at (among other things): improving schools and educational outcomes by using standardized tests to measure what students are learning; holding schools and teachers accountable (through school closures and teacher pay cuts) when their students are "lagging" on those standardized assessments; controlling classroom instruction and increasing the rigor of school curricula by pushing all states to adopt the same challenging standards via a "Common Core;" and using market-like competitive pressures (through the spread of charter schools and educational voucher programs) to provide public schools with incentives to improve.
Critics of the contemporary reform regime argue that these initiatives, though seemingly sensible in their original framing, are motivated by interests other than educational improvement and are causing genuine harm to American students and public schools. Here are some of the criticisms: the reforms have self-interest and profit motives, not educational improvement, as their basis; corporate interests are reaping huge benefits from these reform initiatives and spending millions of dollars lobbying to keep those benefits flowing; three big foundations (Gates, Broad, and Walton Family) are funding much of the backing for the corporate reforms and are spending billions to market and sell reforms that don't work; ancillary goals of these reforms are to bust teacher unions, disempower educators, and reduce spending on public schools; standardized testing is enormously expensive in terms both of public expenditures and the diversion of instruction time to test prep; over a third of charter schools deliver "significantly worse" results for students than the traditional public schools from which they were diverted; and, finally, that these reforms have produced few benefits and have actually caused harm, especially to kids in disadvantaged areas and communities of color. (On that last overall point, see this scathing new report from the Economic Policy Institute.)