They are also organizing a protest on March 7. Get the details here. Their aim is a public education system that focuses on students and teachers, not for-profit corporations. Here's a key quote:
Tests should be written by teachers in Colorado; they are, after all, the experts. Teachers help set the standard of education and must design curriculum in order to teach to the standard. Therefore, they should also be able to see the tests their students take. This way, teachers can give feedback as to how well the test assesses the standard which the students need
to meet. This creates an open, constructive, and transparent dialogue regarding the standards in Colorado, and the tests that determine if they're being met.