average. >> reporter: educators say it takes three to five years for standardized test scores to go up. so far 300 schools have tried it. half would not stick with it. >> this is really hard. superintendents last two, two and a half years on average. it's hard to lead systemic change when you have that much turnover. >> reporter: though state test scores here have not gone up, principal gould is still on board. why? she says discipline problems dropped 76% since the change. and students now are more motivated than ever. debra feyerick, cnn, westminster, colorado. >> we'll examine the crisis in our public education system and why america's future is at risk. a cnn documentary called don"do fail me" will air here on sunday at 8:00 p.m. people have been fighting for years trying to find a