Standardized/Achievement testing has negatively impacted schools in increasingly detrimental ways over the past 50+ years, leading to today's teachers being unable to teach as they see fit.
The Elementary and Secondary Education Act (ESEA) of 1965 explicitly forbade the establishment of a national curriculum. It's ironic that it's current reauthorization, No Child Left Behind of 2001, has effectively done precisely what ESEA intended to prevent. Teachers must "teach to the test" in order to satisfy the demands of administrators who are facing pressure from school boards to improve those scores.
Teachers know it. Parents know it. Administrators and board members know it. EVEN THE STUDENTS KNOW IT!
ESEA and NCLB must not be reauthorized and allowed to continue in their current form.