Sister John Mary Fleming, executive director for Catholic education at the U.S. bishops' conference, told the New York Times that the criticism was misconceived – that the standards should be regarded not as a ceiling, but as a floor.
"We see the Common Core as a minimum, just as we've seen other state standards in the past as a minimum, and we intend to go way beyond that."
Critics, however, have questioned whether shifts in focus and funding will pressure schools to emphasize standardized tests and a narrow set of skills aiming at college preparation rather than comprehensively educating the entire person.
They also question whether the curriculum standards for earlier grades are excessively complex and whether students and teachers have been prepared for the changes.
At present, only math and English Common Core standards have been released. However, the scholars' letter warned that standards in other areas will likely "promote the prevailing philosophical orthodoxies," including a "materialist metaphysics" incompatible with the spiritual worldview that Catholicism presupposes.
"We fear, too, that the history standards will promote the easy moral relativism, tinged with a pervasive anti-religious bias, that is commonplace in collegiate history departments today."
The letter said Catholic officials approved the curriculum with "good intentions" though "too hastily," and with "inadequate consideration of how it would change the character and curriculum of our nation's Catholic schools."
Catholic skeptics of Common Core also include some high school principals. The Cardinal Newman Society, an organization dedicated to Catholic identity in education, surveyed 73 principals of schools that had made its Catholic High School Honor Roll or received honorable mention in 2012.
Of the 60 who responded, almost half thought the adoption of Common Core standards would hurt their school while 23 percent thought it would make no difference, and fewer than 14 percent thought they would improve their school.
Forty percent said their diocese and local Catholic schools should pause and study the standards; almost one-third said they should decline to participate.
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